Question about why people keep rewriting endings to make the bad guy win

I have been hanging around this forum for about 5 months now and I keep seeing the same move over and over. Someone pitches an alternate ending for a book or movie and it is always the villain walking away clean or the hero losing on purpose. I get it, dark endings can hit hard. But when that is the only idea people bring, it stops being a twist and starts being a habit. My buddy Dale does this with everything, I swear he has pitched 9 different endings where the shark wins in Jaws. The one that got me was a thread about The Shawshank Redemption where three people in a row said Andy should have died in the tunnel. That is not a new ending, that is just taking the whole point out and leaving the story with nothing. Anyway I am curious, when you flip an ending like that, what are you actually trying to fix? Because sometimes I think people just want to feel clever instead of making the story better.