I find resting to be always a problematic mechanic in cRPGs (perhaps, that's I actually welcomed that it barely exists in PoE2).

I don't think it can work well without fundamentally altering game's structure. The best implimentation I have seen so far was, I think, Pillars of Eternity1 - a set amount of camp supplies meant devs would know with how many "rests" you would come and could design accordingly - and give you extra supplies if a dungeon was longer. That way they could pace resting, and endurance mechanic meant that depleting HP gave a clear indication when we will be resting, and , at least in my case, it didn't trigger my spell hoarding habit. That is still not without fault, as nothing stops players from overusing rest and trekking back to town for more supplies, nor from barely using their skills. It doesn't quite prohibit unfun play, but at least encourages fun play and gives indications on how to achieve it.

Making resting not available in some ways can backfire - for example I really didn't enjoy Kingmaker for that reason (among many many others). You have to manually decide on how many rests you will carry at any time - amd the game doesn't provide information on which we could make an informed decision. Most of the time supplies are useless, but everyonce in a while one will suffer without a decent supply - but one cannot know that without a foreknowledge making the whole thing frustrating.

I think resting works better in a procedural setting - Darkest Dungeon does it well. When one will misjuidge their rest it might result in a failed run, but it won't halt players progress as such.

For a more handcrafted experience like BG3, I think resting also needs to be to some extend handcrafted. And interesting idea might be (though not fit for BG3) a bonfire system, like in Dark Souls - having resting checkpoints set and having to defeat enemies before reaching the next one (of course respawn is mandatory, as otherwise nothing stop players from cheesing by backtracking, making it not an ideal fit for a game interested in characters and story). I think the best we can hope for is some kind of pacing mechanism. Again, PoE1 I think is good example - encouraging certain pacing, and disencouraging cheese, without prohibiting it. I think Solasta has set resting points, which somewhat serves the same point, but I expect it, again, doesn't prohibit backtracking and cheese (didn't play it, so I can't comment).

In BG3 resting will never be really good, I don't think, as it is a mechanic that runs counter to the world design. Some form of limitation might be nice, but in my personal playthrough I felt I rest rarely, as with backstab and hight advantage spells are mostly an unnecessary bonus, and there were plenty of items to provide healing.