Most of what I've heard so far is kind of generic fantasy and not very Baldur's Gatey.
Well, so was original BG, it was just 90s fantasy generic.
https://www.youtube.com/watch?v=5ZY2mRG5mzgSomething I really liked in BG1 was
diegetic music - how you could hear muted Inn music when getting close to it, making it feel as if it is part of the world. I think this is a real potential there in worldbuilding, that is underutilized. Probably my fav, example is
tavern bard in White March expansion - not only creating wonderful atmosphere, but also at the same time delivering relevant lore and foreshadowing in an inconspicuous way.
EDIT: Found this by accident:
https://www.youtube.com/watch?v=1Q-O-Fftt38EDIT 2: Damn you all. Started flipping through BG2 soundtrack. I forgot how much I adore it.