Git is not slow for me. Don't know about Emacs, but I'm using git from command line and from Idea and it works just fine, instantly for ordinary tasks. Commiting 1000+ files takes few seconds.

Given the fact that Git is used for Windows development with monster monorepository, I think that something's wrong with your setup rather than Git on Windows in general.

Git itself is decent, the problem is that Magit calls git a lot of times for a single GUI action. For some things, it can call git 5-10 times for a single key press. If every git invocation is around 1 second, that becomes a noticeable delay...

That may have been the case in the past, but Microsoft put some effort into making Git faster in Windows.

Also, remember to disable the antivirus for your Git folder!

If only that were up to me... Company laptop, company antivirus, company code...