For me, there's a line between what I see as dark fantasy and horror, and there are some stories that either have a more fantastical element (not particularly horrific) or the MC has so much agency that the darkness or evil or whatever is basically under control. I don't find True Blood an example of horror, since the supernatural elements are used for drama, mostly.
Also, there's a question of effect. Some of the stories lean heavily on familiar tropes and themes, so much so that they lose resonance. I don't want to cite them, since if those are strong stories and continuing on, it would seem like I'm talking down those entries. But if you're doing something very familiar and it's executed in a familiar way, it's easy to shrug and forget about the story. Also, if you can take the horror element out and the story plays more or less the same, then that's a problem for me.
Horror is sort of like the definition of obscenity. You know it when you see it. It is a story that sits in your brain. It makes you physically react. It makes you uncomfortable, and, yes, sometimes disgusted, scared, and freaked out.
