It depends on context. Ideally you have an automatic code review system that would remove a lot of these discussions and create sense that everyone is involved

It depends on context. Ideally you have an automatic code review system that would remove a lot of these discussions and create sense that everyone is involved in the code bases. In this context however it is pretty special because it it was a single commit that that he immediately refactored. In that case the more reasonable approach in my opinion is to take a post-commit code review where you talk to the dude about your thoughts how one can improve the code. It was also a pretty significant change when it comes to coding philosophy, so if you think you know more it is also a potential opportunity to mentor your colleague (or learn something yourself) If it would have been a bug fix or an added feature it is no problem. Or if some time passes and most code is written in style X but this was not and then you rewrite it, also fine.