Something I've noticed with at least some of my friends is that you get people who feel overstimulated by life - stretched thin by responsibilities, by stress, by other personal issues, and a lot of them tend to look for comforting aspects in fiction. Like works that hit their personal comfort zone (often comedy or romance, but really individually variable) and come with a certain sense of safety, like they're not going to have too many negative experiences in the story

And then you get people, more like me recently, who feel understimulated, and tend to crave intensity, and are a lot more likely to enjoy dark work as long as it's interestingly intense dark. And stuff that feels too safe, too predictable, or too intended to be comforting, can worsen the sense of understimulation and boredom.

It's not a Grand Unified Theory of People's Tastes, because I'm sure there's a lot I've left out, but multiple people in my writing group thought it fit their situation, and I thought it was interesting how it was one example of why people's tastes and reactions can vary without anyone being morally superior for liking what they like.