Hey y'all it's time for my favorite segment "I had a thought and I need to vent it out among like-minded people in a lot of letters".
I think it suddenly dawned on me why Karlach's doomed story feels so much worse narratively for some players (like us) than other doomed videogame characters, lacking quest being just an additional insult to injury. This little something that I think a lot us mean when we say "it's unfair", but not really articulate. hence people thinking we just want sunshine and rainbows.
Will hide under a spoiler 'cause it's big, likely spoilery, and also, well, heavy death-related topic incoming.
[snip]
I would put a TL;DR here but I'm not sure how to even phrase it. "Actually, if you think about it, Karlach's tragedy feels worse than some other similar characters or even real situations not just because of the quest lacking or there not being a happy ending, but because it's multiple incredibly heavy tragedies stuck on top of one another in a tower higher than any other character and it's too much when you can't do a thing about any of them"? Something like that.
You're absolutely right that the compounding tragedies make her story feel that much more unsatisfying. Both the "make the most of your finite time" and the "salvation against all odds" plotlines have particular highs that we don't get to experience with Karlach because they're striking a middle ground. They're doing so by taking the lows of the two narratives -- realizing the finality of one's predicament and failing the first two times (before succeeding the third) -- and combining them into one awful experience.
In other words, by the time you've realized you should make the most of your limited time with Karlach, you've wasted most of it by running around trying, and failing, to fix her. So in the end, you've done neither.
I hope the mod who drops by this thread to antagonize us from time to time realizes how frustrating this is.