You suggest pushing the time through actions. But what happens if you've exhausted all the non-combat actions you can take (dialogue, exploring new locations, etc) and only have combat opportunities left, but you have no resources? This risks soft-locking the game.
Ok. I'll explain more thorow how I see it. First of all did you play Dragon Age 2? If you did you may remember how time worked there: it had plenty of timeskips (and that's not very good for an RPG and immersion), but also a frozen world (which we already have in BG3 and we know that there are some players which love its convinience) and quite a lot of quest that were set at different time of a day (something some people want to see in BG3).
So I'm suggesting a hybrid of that with what we already have. Literal actions like walking, managing inventory, looting and smacking someone with your sword shouldn't change the time. Completing quests, considerable main story progress and long rests should change the time, but their time cost should be a bit bloated to compensate those time-free actions.
And if Larian would set certain quest for certain time of a day they can do what Bioware did in DA2: add special time-skip option that activates by player. In DA2 it literally worked like "now you have a quest for the evening while it's morning, either do something else or go to your mansion and time-skip".
So no one would be really soft-locked from anything. If you need to loot some resources you can loot for eternity, if you need to walk back to your camp you can do it, but you cannot pack all quests in one day.
Edit: I'm not necessarily categorically disagreeing with your suggestion to limit things by the game clock. I think it's possible that such an implementation could work, and it'd also provide nice immersion! I'm just trying to address any potential issues so that we can arrive on the best solution, because you know that some people will come in here and use any issues to say "this possible issue is bad and thus long rest restrictions are bad in entirety."
We have partial long rest and for all possible solutions a long rest even partial should skip 8 hours. We have teleports for convenient backtracking.
So I'm not seeing a scenario where a player would stumble on a wall of time, resoursless and not being able to progress further or time-skip.
And what I'm seeing in the suggestion to tie time to long rest that it solves only such things like inns burning for days (not really, because Larian would still need to write a separate script to tell the inn for how many days it can burn), but not things like balance around spell-slots and once-per-long-rest abilities, because you're still keeping the time flow right in the players hands.
