Rest will most likely not be limited (the game isn't designed for limited rest), so the farther in the game, the more powerful casters become.
While for most of the game yes, there is vestiges of things that indicate that limited rest is meant to be something. You can not long rest in the hag dungeon for example which I think indicates that there will be a lot more areas where that is a thing. If there were more areas like that could help with the resting issue and balance things down. Also HP bloat to me is iffy, for certain encounters it works and makes sense while other encounters it is tedious and makes me feel like my casters are doing very very little, it honestly should be a base by base casis. I am fine with creatures deviating from their normal stats and abilities, most every DM does that as it makes it interesting, but sometimes it would be better to stay closer to the original stats with enemies that are meant to be their normal versions.
I suspect that if rest is forbidden in some areas, they will be definitely rare. I doubt if they suddenly forbid resting in a location such as a goblin camp or an underdark there are far too many fights there (I can already imagine how annoying an underdark would be if you had to come back to the surface after each fight).
Most likely, these will be locations with a minimum number of fights, otherwise no one will forbid you to go out and rest outside.
In turn-based games, it is always better to fight a smaller number of powerful enemies, thanks to which the turns take much less time. The last thing I'd like to do is fight the goblin hordes.
These types of fights will become annoying very quickly.
