I get the distress expressed here, but as hardware improves and develops, so does the software: that's life, sadly.
My lady has knitting design software from the '90s that (probably) won't run on Win10, but she keeps an old computer with XP to use it with. Given that old PCs can be bought for peanuts, surely that's the way to go if you want to run old apps?
Regarding Windows 10's alleged install-intrusiveness; I personally found that I didn't have to download it until I wanted to, so I don't understand how this forced install being complained of happened (not judging here, I just don't understand). For my 'puter the install went smoothly; for my lady's (other non-XP, identical machine to mine) it was a struggle; don't know why, but we got there.
All in all I'm happy with Win10. It boots faster, and a lot of (very) old stuff I have still runs: MS is generally pretty good with back-compatibilty. Try that with Mac OS!
Note that the Win10 free install option is soon to be terminated.
Regards -- Mick.
That is supremely irritating when that happens: I get butch about it. Force shutdown by holding down the power button for a few seconds and, like, take that forced update! It picks up again when you switch on again.