I don't know, maybe they could buy White Wolf somehow, or use some other scheme to keep with the D20 vibes via other systems. DC20 though, I could see something there, just because it's similar enough to translate but with a lot less baggage in train.
I don't know if Larian would even want to do such a thing. Given that they have had issues with DnD rulesets when making BG3 (Hence all the homebrew they've done) I honestly question if there's actually any part of the DnD ruleset they actually care for and if they simply wanted the rights to BG3 purely for the popularity that comes with its name.
As far as things go... It's not a particularly compelling system. If offers an unreasonable amout of variance due to the small number of rolls (Especially with the nat 1/20 auto results). D100 based systems are far superior in terms of offering a more reasonable level of variance.
Besides that... There's plenty to be complained about with the overall dice systems in DnD:
Armour can feel useless because it only provides AC and if you're unlucky that does nothing (Not to mention the "Heavy/Medium Armour vs Dex" balance issues)
Weapons often feel bad because limited differences between them (Like, why would someone use a D4 dagger when they can use a D6 shortsword? In prior DnD editions you at least had crit roll differences... But that simply meant you just gravitated towards Rapier, Kukri, Estoc, Scimitar or Elven Curved Blade because these have the same damage dice as other weapons but 18-20 critical threat instead of 20 or 19-20)
Control spells feel terrible because of their "Save or suck" nature. They either work or they don't. Meanwhile damage spells have a lot of save only halves damage instead making them more consistent.
Skill checks are awful and often make no sense. The fact you can hyper specialize your character into doing 1 thing and then they just... Can't do it, makes character creation feel pointless. Even more so when you have dumb things like a master thief can fail to break into the most basic lock ever created, while some pleb can get lucky and break into Fort Knoxx without issue all because of dumb dice rolls. I know some people like the chance to fail as it adds depth to an adventure when you aren't simply master of the universe... But such a thing can still exist without being based on random chance, Pillars of Eternity for example has all its skill checks as simply requirements and if you meet them you perform them. If you don't meet them, you instead get worse options that will lead to less ideal results (Like injuring yourself because you broke down a wall by slamming into it... Because you weren't hench enough to do it easily)
The dice system is great... For Table Top. That's what it is designed for, to be easy enough to use to create an engaging system for TT (And enabling some dynamic player interaction because the DM determines the outcome allowing them to make things more fun). But for video games the system just kind of sucks.
I feel like it's an inevitability now, that someone will want to build on this clearly pretty successful foundation, but I think that would require some other form of continuity or else fans of BG3 may just balk at the effort.
lolno.
BG3 doesn't have any continuation from BG1 or BG2 (Or DA, DA2 or the other DA which in of itself has no continuation from the other 2 DA games). So why would people care if BG4 didn't continue from BG3?
Baldur's Gate games are popular because the setting is decent.
Honestly, quite a lot of people would likely be very happy if BG4 had absolutely nothing to do with BG3. With things like the Steel Watch, Smokepowder being super common, the terrible plot with Emperor/Orpheus being things they'd want the game to stay away from.
The gameplay would probably have to feel somewhat derivative in order to feel like we're still playing a proper sequel along these same lines
Again no.
BG3 has little to do with BG1/BG2 (And again, the 3 DA titles) gameplay wise. BG1/BG2 are RTwP games from an isometric view, DA games are hack and slash ARPG's (The 2 originals are from an isometric view, the modern one is TPP) and BG3 is a TB modern RPG (That is ironically categorised as a CRPG).
BG4 can be whatever genre it wants. So long as the setting is there and the gameplay fits for its DnD basis, it'll work out fine.
