It can be, especially at a company. (But then watch the bikeshed discussion on the tools. And PEP8 is a guideline, not a set of hard and fast rules. Beautiful is better than ugly and all that. ).

What I see as one of 5 maintainers of an open source project is that when a review comes back with a bunch of formatting comments, it's because the reviewer didn't step back and see the other parts. Raymond Hettinger has a talk where he discusses it, but it's the sort of feedback that can be given in almost any case and can obscure the more fundamental issues with the code.