There are 100 reasons that long rests should be restricted to specific locations, and on long rest, minor enemies should re-spawn.
Mainly, you can’t exploit it. It gates player progress in a logical manner for scripting purposes, it builds immersion instead of breaking it.
I think this is a good idea, but I would relegate it as an option for a harder mode or as an option to turn on or off. I did find it kind of jarring to be in a tomb and all of a sudden be at a campsite outside-- I was thinking it would have been reflected that I was in a tomb or something. I was further thinking that I might have had a random encounter too while resting.
