Essentially, yes. In D&D, the whole entire purpose for scrolls is to help provide magic users a supplement for spell slots. They are vital to a magic user so that they can continue to use magic even after they have used up spell slots. The whole point of this is to balance spell casters so they are not carrying the entire party. If you do not limit Long Rest at all in any way, shape or form, Spellcasters wind up becoming an OP member of the team especially at higher levels.
Again, you have to think about all this from a long term perspective. Once the spell caster is able to hurl fireballs and chain lightning all over the map, you NEED to have restrictions in place so that they aren't AOE'ing every enemy in a battle, Long Resting, AOE'ing every enemy in the next battle, Long Resting, AOE'ing every enemy in the next battle, Long Resting, AOE'ing every enemy in the next battle, etc.
Larian has to has to has to correct Long Rest abuse. If they don't, wizards become the MVP's of the game and all other classes become almost obsolete.
So besides it making sense from a story perspective to limit tons and tons of Long Resting, it is vital to game balance to limit Long Resting. The wizard has always, traditionally, been weaker than all the other classes at Level 1-4-ish. As they increase in level and gain more spell slots and such, they become WAY more powerful and WAY more essential to defeating more powerful enemies.
In previous D&D games, my party was carrying the wizard for some time. Then, as the game continued to progress, the wizard was the ONLY way we could defeat enemies. While most of the party was trying to just keep the enemy off of the wizard, the wizard would pummel the enemy with spells.
THAT'S how D&D is supposed to be played. The wizard is a tactically valuable class. You need to wisely use their spells and manage them carefully so that you save your best spells for your worst enemies. You aren't supposed to spam spells every battle on every pathetic minion. The wizard is supposed to help support the other members of the party when fighting minions, but then they go all out on bosses.
So, again, spamming Long Rests just throws all that out the window. Wizards can just spam Magic Missile every battle and always hit and always wipe the floor with enemies. Especially at Level 4, where my characters are right now, I get more slots, so I can have Gale just blast this enemy and that enemy and the battle is over much quicker. Then I can Long Rest, and Gale has all his spells back and on to the next battle. Gale can then spam his spells again and wipe the floor with enemies and Long Rest and so on.
I'm telling you, once you are able to get Fireball, massive groups of enemies will be wiped out like they are nothing, and if there is no limit to the wizard for Long Resting, the game is going to get REAL boring REAL fast. You'll start a battle, Fireball a massive number of foes, clean up the rest with the other party members, and the battle is over. Long Rest, rinse and repeat.
I know this post is not about Solasta, but again, Solasta does this well. You have ONLY select areas where you can Long Rest. So if you spam Fireball and you run out of spell slots, you have to try to get back to some place where you can Long Rest, and Solasta limits your ability to fast travel to Long Rest areas so that you are forced to press on without recovering spell slots. Your fault for using up all of your spell slots, but ultimately the point is that the wizard isn't blasting the crap out of everything every battle. You have to plan out and carefully determine when is the best time to use your spells. The whole point is that you have to carefully manage your resources.
And that's one of the fundamental points of the entire D&D game. You need to carefully balance your resources. That's part of the fun and balance of the game. The point is that you are meant to gather many different types of items for the whole purpose of using them to help you manage everything carefully. Potions, scrolls, magic weapons, etc. are all additional ways that you manage all that you need to get through the quest. You are not supposed to Long Rest after every battle or even all that frequently.
When playing normal D&D, DM's do not typically allow players to fight a battle in a dungeon and then shut the door and Long Rest for the remainder of the day. They fight a battle, if they need it they take a short rest to recover a little, then they move on to the next room in the dungeon. They fight another enemy, take damage, use potions, and move on to the next room. They fight another set of enemies, use spells, heal using potions, etc. and fight the next room full of foes. Ultimately, the entire concept is that you shouldn't actually Long Rest until AFTER you have completed an entire dungeon, and if the DM is a good DM they will build the dungeon in a way so that you don't need to Long Rest until you have completed it. If he sees that you really need a Long Rest, because a battle went particularly wrong, he might create a way to provide you with a Long Rest opportunity at some point just so that he/she can make sure that the characters don't die.
In a video game, this can be done, just as Solasta has proven. As the characters are dungeon crawling, they find an area that is designated as a Long Rest zone. At that point, the characters can Long Rest and recover and then continue. Larian could do something like this as well, but then they'd have to do away with the whole Fast Travel to Camp and Long Rest wherever you feel like it and whenever you feel like it mechanic. This would be harder for them to do because unlike Solasta, BG3 is much more open-world. You can go anywhere whenever you want, which is much more fun to me.
But the tradeoff for having a more open-world is that you need a whole new way to limit Long Rests. The only way I can see that they can limit Long Rests is to have SOMEthing happen if you use too many Long Rests. This brings me right back to the whole concept of the Time Sensitive Long Rest Mechanic that I proposed. You can still Long Rest as much as you want, and explore at your own pace. But the more you Long Rest, which is ending an entire day, the more things move on without you in the world. Things will happen if you Long Rest too much, and negative consequences may occur if you take too many days to complete certain quests.
Honestly, I can't see any other alternative to limit Long Rests, and even in my suggestion I am not truly limiting Long Rests. I am simply proposing that different things happen if you Long Rest more. The fewer the Long Rests you use, maybe the more rewards you get, but if you Long Rest a lot, you may get new side quests and complications in your quests because you took longer to complete them.
So with my suggestion, the idea is that you are technically rewarded either way. If you complete quests with fewer Long Rests, managing your resources more carefully, then you get bigger rewards. If you use more Long Rests and don't manage your resources as well, you get maybe some more fun quest options and see some different events triggered that maybe you wouldn't have gotten if you Long Rested less. In other words, less Long Rests, more rewards like better weapons and armor while more Long Rests things happen like now you need to save Rath from being executed by Kahga, or now you have to help defend the Grove Gate against an attack from goblins or now you have to try to save Wyll from goblins because he foolishly tried to complete his quest without you, or whatever.
In this way, people can still play the game however they want, and they will have different results based on how they play. If they long rest more, they get more complications that they have to solve. If they long rest less, they get more cool items. Either way, the game has WAY more replayability and it is fun either way AND you provide more value to items and short rests and so forth.
So, in my first playthrough, I might try to really go for the no Long Rest approach. In that playthrough, I would get a lot more cool items, but in my next playthrough I might spam Long Rest more and get more fun story quests, because my spamming Long Rest created more story complications...like it should.