What is gssapi-with-mic?
Message Integrity Code.
This is also called a Message Authentication Code, but that acronym gets used for other things, so MIC is less ambiguous. From that Wikipedia page:
The term message integrity code (MIC) is frequently substituted for the term MAC, especially in communications, where the acronym MAC traditionally stands for Media Access Control.
The fix is simple: disable attempts to use GSS-API by adding the following to ~/.ssh/config: