Sure. Considering all the problems with travel at light speed, the vast distance between stars, and a zillion other factors, demons seem like a more plausible hypothesis.
Or they are us and they’re traveling back in time
WHAT MAKES EVERYONE THINK ANYTHING ELSE THAT EXISTS WANTS TO LEAVE ITS OWN PLANET!!?!
Maybe they figure what’s out there might suck so they leave it alone :)
If they were able to view the earth from a distance, i’m SURE of it :)