Re the “killing stuff” paragraph sounds like a memory size issue - frankly, in that case killing something is a better option than desktop linux’s tendency to just freeze the hell up. Just for reference, on a modern low-end samsung I had no such experience.
After 15 years: android’s activity life cycle doesn’t make them constantly save stuff — there is a pause and stop lifecycle events that are appropriate places for saves to happen. Android will attempt to gracefully stop applications, unlike desktop linux’s oom killers. And this model works exceedingly well, you just don’t even notice it, only when it occasionally couldn’t clear enough memory and has to resort to killing.
I haven’t tried doing backups recently, I believe that it is not as streamlined as it should.