"MLM" as in "Marxism-Leninism-Maoism"? I have no idea what this is though. The only mention of it that I have heard was a YouTube video discussing the Philippines years ago.
The other days, there was a guy discussing about Vietnam claiming Vietnamese kids have no idea who Marx, Lenin, and Mao were. Well, I can understand freting over Vietnamese kids not knowing Marx and Lenin, but Mao? Did the guy just ignore the historical disagreement and dispute just for the sake of being alarmist? Tbh, I did not like that guy.
Backup was never optional though. I used to keep clones of Windows because a Windows was hard to set up and running.
But with Linux, I only have to think about my configuration files. Now, even if I nuke my OS, I can still restore it to be close to the original state.
As for documents and other non-OS data, each have their own places.