I started having these issues, which make win10 completely unreliable and thus useless to me:
I'd like to downgrade. Which latest version of windows is reliable--doesn't do restart/sleep/shutdown/hibernate without user approval--and how do I downgrade to it (I don't have any recovery info) without reinstalling from scratch?
I've accepted @Gantendo's answer since he answered the question: it's not possible.
However, I don't agree with him that the OS is stable. Having said that, I'm looking online, and it seems that any OS, even linux, thinks that rebooting without a reason due to a panic is an acceptable solution (who knows, maybe the user won't notice that it made a blunder?).