These long EA periods of time make me wonder if the business model needs to be revamped? The long EA is essentially saying they can't do the massive job in one shot, which really is fine with me. So then lets formally break it into parts and release them one after another.
I don't think it would help anyone. Most titles that go for episodic release are story driven - games with little systemic depth and all about that story. And what I hear (never tried one myself) Telltale style games tend to get disappointing after first couple episodes.
For the BG3 to attempt it they would need to have systems down - and that means combat, as well as stuff like cinematics, AI, interactions outside combat. Those still are worked on, not just story content and maps.
Games of that size take years to finish. That just how it is. BG3 doesn't take much time for an AAA release, nor for an EA release. I am sure that once the game releases, we will be hoping that Larian would delay it for a bit longer anyway
