Magento 2 : When adding 10 (or any number) products to cart with the same sku is there a way to not increment?

If every time want to add a separate product in cart, then you can pluginize representProduct method located in Magento\Quote\Model\Quote\Item

Your [Vendor]/[Module]/etc/di.xml looks like below

<?xml version='1.0'?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd" >
    <type name='Magento\Quote\Model\Quote\Item'>
        <plugin name='beforeDispatch' type='[Vendor]\[Module]\Plugin\Model\Quote\ItemPlugin' sortOrder='99'/>
    </type>    
</config>

and your [Vendor]\[Module]\Plugin\Model\Quote\ItemPlugin.php looks like below

<?php

namespace [Vendor]\[Module]\Plugin\Model\Quote;
class ItemPlugin 
{
    
    public function afterRepresentProduct(\Magento\Quote\Model\Quote\Item $subject, $result)
    {
        if ($yourCondition) { // if there is no condition return always false
             $result = false;
        }
        return $result;
    }
}

You can list all the products with same sku in the same row by overriding quote item model's representProduct() function , which defines how the product will be represented in cart during the creation of quote item itself.

Just add a preference for Magento\Quote\Model\Quote\Item in your di.xml as following ;

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="Magento\Quote\Model\Quote\Item" type="Vendor\Module\Model\Quote\Quote\Item" />   
</config>

and in your Vendor\Module\Model\Quote\Quote\Item add following code ;

<?php
namespace Vendor\Module\Model\Quote\Quote;

use Magento\Framework\Api\AttributeValueFactory;
use Magento\Framework\Api\ExtensionAttributesFactory;
use Magento\Quote\Api\Data\CartItemInterface;

/**
 * Sales Quote Item Model
 *
 * @method \Magento\Quote\Model\ResourceModel\Quote\Item _getResource()
 * @method \Magento\Quote\Model\ResourceModel\Quote\Item getResource()
 * @method string getCreatedAt()
 * @method \Magento\Quote\Model\Quote\Item setCreatedAt(string $value)
 * @method string getUpdatedAt()
 * @method \Magento\Quote\Model\Quote\Item setUpdatedAt(string $value)
 * @method int getStoreId()
 * @method \Magento\Quote\Model\Quote\Item setStoreId(int $value)
 * @method int getParentItemId()
 * @method \Magento\Quote\Model\Quote\Item setParentItemId(int $value)
 * @method int getIsVirtual()
 * @method \Magento\Quote\Model\Quote\Item setIsVirtual(int $value)
 * @method string getDescription()
 * @method \Magento\Quote\Model\Quote\Item setDescription(string $value)
 * @method string getAdditionalData()
 * @method \Magento\Quote\Model\Quote\Item setAdditionalData(string $value)
 * @method int getFreeShipping()
 * @method \Magento\Quote\Model\Quote\Item setFreeShipping(int $value)
 * @method int getIsQtyDecimal()
 * @method \Magento\Quote\Model\Quote\Item setIsQtyDecimal(int $value)
 * @method int getNoDiscount()
 * @method \Magento\Quote\Model\Quote\Item setNoDiscount(int $value)
 * @method float getWeight()
 * @method \Magento\Quote\Model\Quote\Item setWeight(float $value)
 * @method float getBasePrice()
 * @method \Magento\Quote\Model\Quote\Item setBasePrice(float $value)
 * @method float getCustomPrice()
 * @method float getTaxPercent()
 * @method \Magento\Quote\Model\Quote\Item setTaxPercent(float $value)
 * @method \Magento\Quote\Model\Quote\Item setTaxAmount(float $value)
 * @method \Magento\Quote\Model\Quote\Item setBaseTaxAmount(float $value)
 * @method \Magento\Quote\Model\Quote\Item setRowTotal(float $value)
 * @method \Magento\Quote\Model\Quote\Item setBaseRowTotal(float $value)
 * @method float getRowTotalWithDiscount()
 * @method \Magento\Quote\Model\Quote\Item setRowTotalWithDiscount(float $value)
 * @method float getRowWeight()
 * @method \Magento\Quote\Model\Quote\Item setRowWeight(float $value)
 * @method float getBaseTaxBeforeDiscount()
 * @method \Magento\Quote\Model\Quote\Item setBaseTaxBeforeDiscount(float $value)
 * @method float getTaxBeforeDiscount()
 * @method \Magento\Quote\Model\Quote\Item setTaxBeforeDiscount(float $value)
 * @method float getOriginalCustomPrice()
 * @method \Magento\Quote\Model\Quote\Item setOriginalCustomPrice(float $value)
 * @method string getRedirectUrl()
 * @method \Magento\Quote\Model\Quote\Item setRedirectUrl(string $value)
 * @method float getBaseCost()
 * @method \Magento\Quote\Model\Quote\Item setBaseCost(float $value)
 * @method \Magento\Quote\Model\Quote\Item setPriceInclTax(float $value)
 * @method float getBasePriceInclTax()
 * @method \Magento\Quote\Model\Quote\Item setBasePriceInclTax(float $value)
 * @method \Magento\Quote\Model\Quote\Item setRowTotalInclTax(float $value)
 * @method float getBaseRowTotalInclTax()
 * @method \Magento\Quote\Model\Quote\Item setBaseRowTotalInclTax(float $value)
 * @method int getGiftMessageId()
 * @method \Magento\Quote\Model\Quote\Item setGiftMessageId(int $value)
 * @method string getWeeeTaxApplied()
 * @method \Magento\Quote\Model\Quote\Item setWeeeTaxApplied(string $value)
 * @method float getWeeeTaxAppliedAmount()
 * @method \Magento\Quote\Model\Quote\Item setWeeeTaxAppliedAmount(float $value)
 * @method float getWeeeTaxAppliedRowAmount()
 * @method \Magento\Quote\Model\Quote\Item setWeeeTaxAppliedRowAmount(float $value)
 * @method float getBaseWeeeTaxAppliedAmount()
 * @method \Magento\Quote\Model\Quote\Item setBaseWeeeTaxAppliedAmount(float $value)
 * @method float getBaseWeeeTaxAppliedRowAmnt()
 * @method \Magento\Quote\Model\Quote\Item setBaseWeeeTaxAppliedRowAmnt(float $value)
 * @method float getWeeeTaxDisposition()
 * @method \Magento\Quote\Model\Quote\Item setWeeeTaxDisposition(float $value)
 * @method float getWeeeTaxRowDisposition()
 * @method \Magento\Quote\Model\Quote\Item setWeeeTaxRowDisposition(float $value)
 * @method float getBaseWeeeTaxDisposition()
 * @method \Magento\Quote\Model\Quote\Item setBaseWeeeTaxDisposition(float $value)
 * @method float getBaseWeeeTaxRowDisposition()
 * @method \Magento\Quote\Model\Quote\Item setBaseWeeeTaxRowDisposition(float $value)
 * @method float getDiscountTaxCompensationAmount()
 * @method \Magento\Quote\Model\Quote\Item setDiscountTaxCompensationAmount(float $value)
 * @method float getBaseDiscountTaxCompensationAmount()
 * @method \Magento\Quote\Model\Quote\Item setBaseDiscountTaxCompensationAmount(float $value)
 * @method null|bool getHasConfigurationUnavailableError()
 * @method \Magento\Quote\Model\Quote\Item setHasConfigurationUnavailableError(bool $value)
 * @method \Magento\Quote\Model\Quote\Item unsHasConfigurationUnavailableError()
 * @SuppressWarnings(PHPMD.CouplingBetweenObjects)
 * @SuppressWarnings(PHPMD.ExcessivePublicCount)
 * @SuppressWarnings(PHPMD.ExcessiveClassComplexity)
 */
class Item extends \Magento\Quote\Model\Quote\Item
{
    /**
     * Prefix of model events names
     *
     * @var string
     */
    protected $_eventPrefix = 'sales_quote_item';

    /**
     * Parameter name in event
     *
     * In observe method you can use $observer->getEvent()->getObject() in this case
     *
     * @var string
     */
    protected $_eventObject = 'item';

    /**
     * Quote model object
     *
     * @var \Magento\Quote\Model\Quote
     */
    protected $_quote;

    /**
     * Item options array
     *
     * @var array
     */
    protected $_options = [];

    /**
     * Item options by code cache
     *
     * @var array
     */
    protected $_optionsByCode = [];

    /**
     * Not Represent options
     *
     * @var array
     */
    protected $_notRepresentOptions = ['info_buyRequest'];

    /**
     * Flag stating that options were successfully saved
     *
     */
    protected $_flagOptionsSaved;

    /**
     * Array of errors associated with this quote item
     *
     * @var \Magento\Sales\Model\Status\ListStatus
     */
    protected $_errorInfos;

    /**
     * @var \Magento\Framework\Locale\FormatInterface
     */
    protected $_localeFormat;

    /**
     * @var \Magento\Quote\Model\Quote\Item\OptionFactory
     */
    protected $_itemOptionFactory;

    /**
     * @var \Magento\Quote\Model\Quote\Item\Compare
     */
    protected $quoteItemCompare;

    /**
     * @var \Magento\CatalogInventory\Api\StockRegistryInterface
     */
    protected $stockRegistry;

    protected $scopeConfig;

    /**
     * @param \Magento\Framework\Model\Context $context
     * @param \Magento\Framework\Registry $registry
     * @param ExtensionAttributesFactory $extensionFactory
     * @param AttributeValueFactory $customAttributeFactory
     * @param \Magento\Catalog\Api\ProductRepositoryInterface $productRepository
     * @param \Magento\Framework\Pricing\PriceCurrencyInterface $priceCurrency
     * @param \Magento\Sales\Model\Status\ListFactory $statusListFactory
     * @param \Magento\Framework\Locale\FormatInterface $localeFormat
     * @param Item\OptionFactory $itemOptionFactory
     * @param Item\Compare $quoteItemCompare
     * @param \Magento\CatalogInventory\Api\StockRegistryInterface $stockRegistry
     * @param \Magento\Framework\Model\ResourceModel\AbstractResource $resource
     * @param \Magento\Framework\Data\Collection\AbstractDb $resourceCollection
     * @param array $data
     *
     * @SuppressWarnings(PHPMD.ExcessiveParameterList)
     */
    public function __construct(
        \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig,
        \Magento\Framework\Model\Context $context,
        \Magento\Framework\Registry $registry,
        ExtensionAttributesFactory $extensionFactory,
        AttributeValueFactory $customAttributeFactory,
        \Magento\Catalog\Api\ProductRepositoryInterface $productRepository,
        \Magento\Framework\Pricing\PriceCurrencyInterface $priceCurrency,
        \Magento\Sales\Model\Status\ListFactory $statusListFactory,
        \Magento\Framework\Locale\FormatInterface $localeFormat,
        \Magento\Quote\Model\Quote\Item\OptionFactory $itemOptionFactory,
        \Magento\Quote\Model\Quote\Item\Compare $quoteItemCompare,
        \Magento\CatalogInventory\Api\StockRegistryInterface $stockRegistry,
        \Magento\Framework\Model\ResourceModel\AbstractResource $resource = null,
        \Magento\Framework\Data\Collection\AbstractDb $resourceCollection = null,
        array $data = []
    ) {
        $this->scopeConfig = $scopeConfig;
        // $this->registry = $registry;
        // $this->extensionFactory = $extensionFactory;
        // $this->customAttributeFactory = $customAttributeFactory;
        // $this->productRepository = $productRepository;
        // $this->priceCurrency = $priceCurrency;
        $this->_errorInfos = $statusListFactory->create();
        $this->_localeFormat = $localeFormat;
        $this->_itemOptionFactory = $itemOptionFactory;
        $this->quoteItemCompare = $quoteItemCompare;
        $this->stockRegistry = $stockRegistry;
        $this->resource = $resource;
        $this->resourceCollection = $resourceCollection;
        parent::__construct(
            $context,
            $registry,
            $extensionFactory,
            $customAttributeFactory,
            $productRepository,
            $priceCurrency,
            $statusListFactory,
            $localeFormat,
            $itemOptionFactory,
            $quoteItemCompare,
            $stockRegistry,
            $resource,
            $resourceCollection,
            $data
        );
    }

    public function representProduct($product)
    {
        $itemProduct = $this->getProduct();

        if (!$product || $itemProduct->getId() == $product->getId()) {
            return true;
        }

        if (!$product || $itemProduct->getId() != $product->getId()) {
            return false;
        }

        /**
         * Check maybe product is planned to be a child of some quote item - in this case we limit search
         * only within same parent item
         */
        $stickWithinParent = $product->getStickWithinParent();
        if ($stickWithinParent) {
            if ($this->getParentItem() !== $stickWithinParent) {
                return false;
            }
        }

        // Check options
        $itemOptions = $this->getOptionsByCode();
        $productOptions = $product->getCustomOptions();

        if (!$this->compareOptions($itemOptions, $productOptions)) {
            return false;
        }
        if (!$this->compareOptions($productOptions, $itemOptions)) {
            return false;
        }
    }
}

For explaination I have just added following condition in representProduct() function

if (!$product || $itemProduct->getId() == $product->getId()) {
            return true;
        }

Please note that the this will apply to new quote items created and not the old ones that are already present in cart.

Feel free to ask any questions if required.