I love BG series since I'm young (started playing bg1 when I was 14, and I was still playing this year). While BG3 is different in many respect, it is honourable to the franchise IMO.
The game is different obviously, because 20 years have passed. Beamdog made a remaster is what you want is the original game. And BG3 shares a lot with divinity original sin, mostly because it's the same engine running it. It's not real time with pause, you have far more interactions with the environment, far more possibilities while exploring the world, and the world is far more reactive to what you're doing.
IMO BG3 is better than bg2 in almost every respect.
The companions relationships are deeper, and they still have their own personalities, they're not just following you like in almost all bioware games post BG. There can be very dramatic moment with them.
The rest of the game has a lot to do with what made BG good games. And there was a lot to it.
An important part was the dnd fantasy world and rules. They are updated to 5e, and it's still dnd, no other game than a dnd franchise would have that.
Most other aspect were already there in Dos2 though: exploration, character and group building, itemization, open world and big side adventures. All that is there and it is the quality of BG. The freedom to do anything the way you like is also there and better than with BG, because the engine allows so much more.
The tactical aspect is also there. The only difference, as I said, is turn based instead of real time with pause. If you're OK with that, I cannot see how you wouldn't be happy with BG3, except for some nostalgia that would prevent you from liking anything new. IMO BG3 is factually a better bg2.
Lastly, the story. I'm not that far, and I haven't seen many connections with bg1 and 2 stories yet. There are references. And the story happens around and in Baldur's gate (unlike Baldur's gate 2 btw).