I don't typically review commit by commit, but I do really appreciate having good commit messages when I look at the blame later on while reading code.

Indiscriminate squashing sucks. Atomic commits are great if you want the git history to actually represent a logical changelog for a project, as opposed to a pointless literal keylog of what changes each developer made and when. It will help you if you need to bisect a regression later. It sucks if you bisect and find the change happened in some enormous incohesive commit. Squashing should be done carefully to reform WIP and fix type commits into proper commits that are ready for sharing.

It is often easier to review commit-by-commit, provided of course that the developer made atomic commits that make sense on their own.