Eh, there's a huge difference between having AI fix a bug and fixing a bug.
The latter implies that you've understood where and how it happens as well as noticed any other areas that may be impacted by fixing the bug or by not fixing it. AI just fixes it without thinking about anything else - which is great, but it explains why serious people (and Microsoft) aren't doing just that. We've spent decades worrying about quality, reliability and performance. Using AI is saying all of that was poppycock and it's faster to rebuild than to understand and fix. It's a different school of thought, and hopefully one that bursts down in flame in a few months.
This is not why your "serious people (and Microsoft)" aren't fixing this stuff.
They don't fix this stuff, because it's a priority-3 ticket sitting in the middle of the queue that has hundreds of similar tickets on it, and none of them are being done, because the team has moved on and is either developing new stuff, or addressing priority-1 bugs that are blocking the other teams that are developing the new stuff (possibly backend stuff, but still stuff that will bring money).
The kind of bug that can be fixed by overwriting instructions with NOPs is trivial. The OP isn't trying to invalidate Microsoft's SDLC & QA. They just wanted a solution.
Who says inserting those NOPs didn't break other behaviour that OP isn't using. And then there's also Hyrum's law. This whole thing could be very non-trivial.
Fixing a bug for everyone is very different from fixing the bug just for yourself