Personally for me, I'm never going to include heavily taboo topics that are borderline fetish-like and off-putting. Some people have already mentioned some of them, and I think most of us know a few others. Mostly because my stories don't thrive off those topics, regardless of whether or not I properly handle them. They're just not needed for what I create.
That said -- I have written stories that dealt with abuse. I've always provided warnings for those stories, and I did my research beforehand. For me, if I'm doing a story about abuse, I'm not going to just pop it in just because. It has to be a key part of a character's development and interactions.
The one thing that pulls me out of a story is when the creator pops in touchy topics that legitimately could've been left out. A few times, I've read stories with graphic displays of sexual assault, and it really didn't move the plot or the characters in any way. If anything, it ruined the stories because it felt like it was just put there for shock value, if not a bit romanticized. I can't really say what the creators' intent were, but from a reader's perspective, that's what I felt.
I don't mind creators exploring those topics, even if some are off-putting to me. Hell, I know some people might not read my stories with abuse in them. But at the very least, there's some sense of duty on how we handle them and how we provide some warning labels. Think of it as the ratings for movie trailers:
It's one thing for someone to watch a movie with graphic violence but was warned beforehand.
It's another when there's no warning at all.