You're implying that Larian have actually been evolving with each game. Which is not necessarily the case (Especially since most of the improvements from DoS2 to BG3 are simply just using the DnD ruleset instead of Larian's own thing).
You're also implying that a "BG-esk" game requires Larian's level of competence. Which is not the case (And is arguably not a particularly high competence when you account for the whole "Act 3 sucks" thing that is prevalent in Larian titles)
BG3 is not some unreachable level of video game expertise. It's simply the first AAA CRPG, that happens to also be using a very big IP.
Yes. There is a bit jump in complexity from D:OS1 to D:OS2 nad D:OS2 to BG3.
I thing you are confusing not liking Larian design (which I am there with you), and the scale of what Larian is delivering. Yes, it is „just the first AAA cRPG”, but those dont appear from a thin air. You need tools, production pipeline, staff experienced with working with those tools and production set up making that type of game.
Yes, there are third party engines, but the question is if those engines are set up well enough to support a niche design like turn-based top down game, or would require a ton of customisation and support. Of course everything comes down to money, but I wonder how many publishers outside of Sven and his independent company would be willing to invest so heavily into such narrow genre. Maybe they will, maybe they won’t. Anyway, here is Tim Cain talking pron and cons of using custom vs of the shelf engine:
I would love for other companies to do bigger budget cRPGs. I would kill for AA-AAA Pillars of Eternity3 for example. larian’s sensibilities unfortunately don’t appeal to me personally. At the moment, however, only Larian seems to be equipped for doing AAA cRPG. Everyone else would have a lot of scaling up, training and R&D to do.
I am all for AA-AAA cRPG wars, though. I can take all they throw me.
