Handling Pushback in Code Reviews

The best way, IMHO, is to have coding standards, a check list on what is to be checked in code review, including set of tests that must pass, and a clear rule that a commit must have a single purpose (e.g. if an unrelated bug is found in a code review, great, raise a bug report to be addressed in another, dedicated commit).

Then, personally I am all for ignoring suggestions based on personal preferences. Often there are several ways to achieve the same thing. As long as the way something is implemented works, ticks all the boxes, and does not create a provable issue right now, then it's fine and there should not even be a suggestion to do differently in a code review.

The general idea is to get rid of as much comments and suggestions based on personal preferences and to focus on fact-based comments, which tend not to generate arguments.