Yeah, 20 hours for Rimworld seems impossible. I never got to the endgame, and I think on one playthrough I had something like 70+ hours before my colony collapsed. The game is hard.
Good to know about ME:A; I was a huge fan of the original ME trilogy, but didn't pick up Andromeda because reviews made it feel like not worth the time and emotional investment. Maybe I'll reconsider.
I didn't mean winning though. I meant closure, as in you can crash and burn and still have fun. If you went through 20 hours of failing in Fallout 4, it wouldn't nearly be as fun.