Wouldn't these types of changes more commonly be caught while testing against a branch? Also in many cases I would think that the fix ends up being even smalle

Wouldn't these types of changes more commonly be caught while testing against a branch? Also in many cases I would think that the fix ends up being even smaller (or bigger) than a single commit (the commit isn't actually atomic). Maybe the codebases I've worked on weren't active enough for this to be a common problem. But also, having too many cooks in the kitchen may be a part of the problem here too.