The only issue with rebasing is if someone else has checked out the branch and now they have diverged. It's usually a simple fix, but it can get annoying.

I tend to checkout branches to do code reviews, when changes are complex a diff is not enough, I want an IDE to help me reason about the code (I sometimes even refactor and try different things just so I can understand the code better, so I can make good suggestions).

When I do this, and comment, and the other dev rebases, it's an extra step for me on the next CR cycle.