I'm at least speaking from daily use in my anecdotes. Apples for apples, yes Windows is going to lag behind Linux. [1] That doesn't mean it isn't fast and stable from the perspective of day-to-day Windows usage, and definitely as I stated in the previous comment, it is much faster and more stable on Windows today compared to Windows a few years ago.

Several of the anecdotes on the reddit thread don't even seem to take account what version the offending slowness was happening in, and anecdotally every time I've helped a Windows user experiencing slowness enough to complain about it, they've been years behind on their git version and installing the latest removed the complaints.

[1] ...and is just about guaranteed to in the many places in git where a command is still built as a tower of bash scripts calling perl scripts calling more bash scripts... If you read the changelogs, a lot of the performance optimizations that are helping every platform are the places where entire commands are getting replaced with C versions of themselves.