Quite a bit, actually! Here's some fun facts of mine:
Drizzt *is* still Drizzting, thank you for asking!
Tech's more or less the same, but there's the odd flintlock pistol kicking around now.
Politics are a bit different in a few ways. The Zhents are way less coherent now, being less a shadowy cabal of thugs and wizards and more of small cells of a mafia without any coherent direction. They even come into conflict with other Zhent groups every now and again.
A lot of the bigger cities along the Sword Coast (Waterdeep, Neverwinter, Baldur's Gate, Mirabar and Elturel, to name a few) formed the equivalent of the UN dedicated to keeping the roads and trade safe. One of the more important figures is Lord Dagult Neverember, who is a grade-a asshole who currently rules Neverwinter (Still recovering after a natural disaster) and used to be Open Lord of Waterdeep. He was an embezzling racist who I personally dislike. Laeral Silverhand, an old friend of Khelben Blackstaff now rules Waterdeep as its open lord. The fellow who was kidnapped, Grand Duke Ulder Ravengard, represents Baldur's Gate in the Lord's Alliance and leads the Flaming Fist. Honestly, this isn't the first time he's been kidnapped, probably because he's so competent taht with him in charge the Fist can usually sort things out.
A lot has happened since Descent into Avernus. Two whole editions, in fact! A ton of gods are back too, including the Dead Three, which means that Bhaal is actually alive after the last Bhaalspawn was killed and his divine essence freed. Mystra died and came back again in the time since the original Baldur's Gate games. A bunch of other stuff happened, but this is just the stuff off the top of the ol' dome.
