"Larian replaced the original F tier ending that ignores players' choices with a D tier ending that also ignores players' choices, plus we can fix anyting using our imagination, therefore they listened."
They didn't, or they did and just didn't care. After almost 1 year, Karlach's quest is still marked as "failed" in the game file, her mission is still a glorified fetch quest except the items you fetched go no where, all the foreshadowing in early chapters still leads to an abrupt dead end, she still only got second least content which is only slightly more than Wyll (whose content is only half of Larian's favourite Astarion). Swen Vincke straight up said on his twitter that their game "doesn't need anything more" and they're happily handing Karlach's fate over to WotC.
Not agreeing with the "Karlach deserves it" dude because she definitely deserves better, like, a lot, but the cope here is just a bit funny. The game didn't change itself, you just changed your mind, it's called compromission.