As our Harvey Randall wrote, we're all still playing Baldur's Gate 3 more than a year after its release because there's so much to find in it.
Gale can write a sad resignation letter if you ignore him long enough, and there's a game over just for people who go out of their way to lose a plot-critical item.
When I was playing I triggered an ambush by Astarion's vampire-spawn siblings by long-resting repeatedly in the Lower City, something that apparently a lot of other players didn't experience.
Even I didn't notice what happens if you let Astarion get vamp-napped, however. As documented on the Baldur's Gate 3 subreddit by Soft_Stage_446, Astarion gets taken to his master's torture kennel to be punished by a skeletal interrogator called Godey.
An entire scene you'd otherwise never see plays out from Astarion's point of view, whether or not you chose to play him as your origin character.