It's sad, so it sucks.
A work is widely panned by viewers and/or critics not because of the work's quality, but because it's depressing
There are a lot of reasons people might not like a show, movie, game, book, etc. Maybe the visuals aren't that stellar
. The actors might not be that great
. The plot is poorly written. It gives a terrible message to the viewers
(If there's even a consistent message in the first place
). I could go on, but there's one other quality that might turn people away from what might otherwise actually be a pretty decent work. The story has a sad ending. No one wants to watch a movie that ends with the underdog being left with nothing while the big, powerful villain gets everything. Reasoning behind this train of thought is probably because there isn't much enjoyment in re-watching a movie or re-reading a book if you know that it's all gonna end in ruin.