Why can't we have all the endings? Ignoring pragmatism, because not all of them make sense. Remember that guy that spent his entire adult life trying to ressurect a skeleton in his basement and failing, even though he had access to one of the most powerful books on Necromancy in existance? Remember Mayrina that made a deal with a hag to try and get her husband back? Remember what Ketheric Thorm had to do in order to bring his daughter back?

THAT is the world the game is set in. Why SHOULD your Tav succeed when saving Karlach isn't even Tavs main focus? Why can't one companion die because they refuse to do the one thing that will save them? Avernus was a choice, which Karlach refused in the original version, because "It would be worse than death". I would have been fine if the writers let her die with dignity after she saved Faerun and was brave enough to choose death over servitude, but now the fan-service is done and y'all can have an ending where Karlach lives and fits with the world that Larian built. What people are asking for now is the unreasonable and the unplausible.

@Nary a care: This game is a work of art, not therapy. Larian had a story to tell. Just like with everything else (including PnP D&D) - don't bring your personal trauma into other peoples lives uninvited. Karlach's story isn't yours. No one has the right to make demands of the writers.