Being able to rest anywhere - as often as you want - sucks tension out of the game. Risk free resting everywhere is also something that earlier BG games didn't have, and means that you needed to..you know...plan things. And not just spam all your most potent abilities. Not having it, even on Tactician, is not really defensible. A well designed game and encounter sequence pushes you hard enough so that you can *just* make it, if you manage your resources - I never felt threatened in BG3. And adding things like those angelic potions - that mean even when you can't rest...you *can* actually rest - is another poor design choice.
One thing they could do is to make those "red map zones" where you can't fast travel or go to camp more common, at least on Tactician. It won't fix short rests or potions, but it would help bring some tension back. On Tactician, that should probably be the default state in "hostile areas" like the Goblin Camp. So without doing a full retreat from the area, you'd only have your short rests. And they could just tie it to the difficulty, because then it wouldn't necessarily make things worse for those who just want an easier experience.
Another thing that could be done is to make a lot of spells / elixirs last "until the next long or short rest", so short resting would require you to reapply your buffs. And make Angelic Potions "corrupted" or "spoiled" on Tactician.
Of course, I do think that fixing a lot of the broken, overpowered and underpowered (mostly just human, admittedly) options in the game would also make it easier to improve the balance.
In BG, IWD etc., you could rest anywhere as well, but you had a chance to be ambushed... just reload and rest again - done. Not a good system.
In NWN you can just sit down and rest in a corridor for 5 sec and you're good to go blasting meteor showers and horrid wiltings on them bandits in the next room.
It's only ToEE that punished resting in a wrong place really hard - you still could do it, but you would be ambushed 100%, unlike BG, where it was a coin flip. You absolutely had to get out of that maze of a temple, search for shortcuts and go rest in an inn. Gotta admit, the tension because of this was high. And it did not feel like a chore - you had to be careful, plan your resources and think about every spell slot - "is it worth to use now, or we can go without and save it for something more dangerous".
At the same time, Temple of Elemental Evil is a pinnacle of DnD dungeon crawling, so can't really compare BG3 to it.
Imagine now in BG3 there are no portals to move around and no fast travel and no possibility to just port to camp when you need to rest - you have to run to a hub for resting. Or use Larians pyramid to port back to a safe spot? Will the game be better? Don't think so.
It's our choice as a player to rest whenever we want - do it after every encounter or limit yourself to rest in a way that makes sense from RP perspective.
Resting has always been a very weird thing in various games using or inspired by D&D and rarely function all that well, be it in the player's or enemy's favor. BG1 is terrible with resting, while BG2 feels like it is expecting you to rest a lot.
I legit think systems like those in the Dragon Age series are fairly reasonable though. In DA: Origins and DA2, you regenerate everything (health, stamina, mana, cooldowns etc) automatically after combat, save your "wounds" and consumables, but in return the game also builds encounters on the assumption that you're always at full strength.
The other side of that is DA: Inquisition, which doesn't let you heal without consumables at all (save some very rare abilities), limits how many healing consumables you can have, but you get everything back while camping. However, just about every enemy respawns and you can only rest in specific locations (camps, fast travel points) and you'll just have to go through the same enemies to get to where you were. So while resting is "free" and super convenient, it does reset your progression. The only way to rest and progress is to find camps and fast travel points. You can also find "supply caches" that'll let you use your potions with a free refill, but these are single use.
