Further to upgrades - I bought a refurbished/upgraded Windows 11 PC a few months ago and it was fine until a document I was working on suddenly locked up. I used Ctrl Alt Delete to see what was going on and then found Windows was updating itself. Unfortunately the system locked up as well and after half an hour I had to do a hard shut-down. Then it wouldn't boot into Windows and over the next couple of days I tried everything to fix it with the Windows repair options. Nothing worked, even System restore showed no saved points and a recovery disc wouldn't go any further because of a missing file (how could that be?).
I had to format the drive with a downloaded ISO and when I eventually got W11 back, I'd lost the MS Office 2019 that had been included in the bundle. Then found out in BIOS that there was no Trusted Platform Module 2.0, which was supposed to be essential for W11, Enable Secure Boot had been disabled and the processor was not on the support list. I'm guessing that the minimum requirements had been bypassed by the registry hack. Secure Boot has got it back into action but for how long if the updates decide otherwise...
So - I'd suggest that anyone thinking of buying a PC upgraded to W11 should check on its specs first.