So if you managed a team, and when you look at commit histories you notice that one person has <1 commit a month and you look at the commits and they're trivial... you would disregard any concerns?

The answer is still "it depends", I would imagine that issues would arise well before you had to look at their commit history.

I believe that if you are a good manager, you would just need to look at what tickets get done during the sprint and that's it. If you complete your tickets and pass QA/UAT in 10 LOC, so be it. There is no need to micromanage.

I would wonder how it got to the second month, certainly - getting to the point where this kind of post-hoc analysis can actually be done is a serious failing of management.