There is really no way to implement a meaningful limited rest system without running the risk of ruining playthroughs.
Shall we try again?
1) Let people set amount of their Camp Resources (including or excluding food) in difficiulty settings, including 0.
2) Set specific locations wich are the only places that count as "safe enough" for our party to rest ... again, let people enable/disable this in Difficiulty setting.
3) Let people set amount of encounters per Long Rest ... you wish to fight once, twice, thrice, four...ice?

Whatever ... you set it, and thats when Long Rest will be enabled for you, not a moment sooner ... and it probably dont surprise you, but yes, this should also belong to difficiulty settings.
Whoah ...
What would you say, it took me like ... how much a minute?
Maybe two ... and i found out three ways that "dont exist".

If you are a new player and still figuring out the game and you soft lock yourself out of being able to progress and need to roll back to a prior save losing hours of progress or maybe even completely start the game over from scratch
Sure ...
OR!
Just open your difficiulty settings, and change them?

Seems easy enough to me, i would almost call it intuitive.

Have you ever concidered to follow your own advice?
Im just curious.