Android - Remove Most Frequently Used Apps Container from Apps menu

To remove the most used app bar follow the steps :

  1. Open Google Now ;
  2. Open the sidebar (hamburger menu or slide from the left) ;
  3. Click the "Settings" button ;
  4. Scroll down to the Home screen section
  5. Toggle the option "App Suggestions".

Source : Reddit.

There was recently an update (Android 7.1.2) that makes the previous answer incorrect, the new directions are as follows:

  1. Press and hold on the home screen until this dialogue appears:
    1. Then simply press the settings icon and change the one that says app suggestions.

Source: experimenting