I'm having the exact same problem. I've done the registry fixes and clearly that didn't work. I'm now automatically downloading Win 11 despite altering all the registry keys to make that impossible.
I tried 11 and I HAtE IT. I got two crashes in 10 minutes, there's no way to put the screens on Dark Mode so I can read them more easily, and they've fubared the GUI. The glare from no Dark Mode alone started giving me a headache as it's difficult for me to read black text on a white field due to cataracts. NOT COOL, people!
WTH, Microsoft? Why are you shoving a broken product down our throats and not giving us a choice as to whether or not we want to change to Win 11. I can't call it an upgrade with a straight face.
I want Win 11 to stop downloading and I want it NOW.