Regardless, neither of them is particularly strong on choice and consequence.
BG3 is very strong on choice and consequence. I'm not sure how anyone who has played the Early Access can say otherwise. Just look at the dialog checks, something even BG had precious few of.
Like most such "cinematic rpgs" the C&C really comes down to different dialogue responses and choices.
You should say "like most RPGs", since that's usually the case in every CRPG. But stat checks aren't limited to dialog. Look at the hag quest, where whether or not you see through the illusion spell cast on an entire area of the map is determined by a perception check.
Also, on plot, BG1 and BG2 always have the exact same plot progression for the main quest. BG2 adds one skippable area, the Sahuagin city, and lets the player chose how to get to the Asylum, but ftmp leads the player down a linear path they have little choice on. Whereas BG3 still retains some linearity (I *think* you always have to go to Moonrise Tower at some point, but I'm not sure), but gives you multiple paths and choices along the way just in Act 1. Side with the goblins, side with the druids, side with no one. Take the Underdark route, take the overworld route. And these are just the choices that I know about for sure.
Then there are all the other choices you can make as side quests that can wind up affecting the game - e.g., whether or not you get a hag eye, and which companions you bring along, leave behind or kill. Compare that to BG1 or 2, where the side quests basically determine what loot you bring along.
Yeah, I'm not sure how you can say that at all.
Really we need a procedural non IP RPG with a strong character and social simulation where things can happen organically. Probably about 20 years away though, technology wise.
We basically already have that. It's called PnP. And if you don't want to interact with a human, you can have GPT-4 be your DM.