I consider bittersweet endings to be the most memorable ones. The best endings I remember in fantasy stories was of course LOTR and Malazan Book of the Fallen.
The issues I had with BG3 endings were (no spoilers):
1. Cut brutally short. Let us savour those moments. Let it sink it.
2. Very bitter and little sweet for some characters.
3. Shallow and not reflecting the plethora of choices we've made with our heroes (or villains?) during the stories.
BG3 allows everybody to create a character and narrative that just belongs to you and it is wonderful. I think that endings should reflect that. Do you want to be the hero that saved the day? Sure thing, run extra mile, find a way and make people happy. You need a bittersweet one, as there is no victory without sacrifice? Sure thing, it is your story. You want a dark ending? Embrace it.
The game deserves that final cherry on the cake like no other game in the last decade.
