Well, Karlach death does remind me somewhat of Aerith, back in 1997...
You don't have to like it, the game designer doesn't have to fix it either.
I do think all characters should be okay with Karlach in Poly, because they understand she's got weeks to live at best and could die at any time. Indulge her before time is up.
Except FFVII isn't a crpg by any means and a very different game in the way it handles decisions, Aerith didn't get impaled by Sepiroth while the others got to walk away free just 'cause, she died to propel the story forward in the way that it was written. it's a gut punch nonetheless, but it's still implemented in the story in a very different way when we compare it to Karlach. Karlach has no fix while there are multiple hints scattered throughout the game, and she exists in a context where multiple companions are a on a very shitty path, only to be saved or nudged towards a kinder fate by the player. No companion suffers the same grim possible fates without a possible kinder and brighter one, she's the odd one out. Karlach's death/ceremorphosis/return to avernus (mostly her death) serve no purpose narratively, when we analyze in the context of this specific game. FFVII has a very linear story and the fate of companions aren't nearly as mutable as bg3. I do see your point, mind you... and her death MIGHT have worked had it been implemented diffrently, but i personally don't think this is the case.
