Fiction is not reality.

You can enjoy things in fiction that would be awful in the real world. Like playing a murderhobo in a game! In the real world, being or supporting a murderer-thief would be pretty damn awful, while in the game it's just good fun. Same with anything else you choose to do with the pixels on the screen, like kinks that don't affect anyone real, so they're okay in fiction, but would be pretty damn bad in real life.

No one else is responsible for your online experience. They are required not to harass you, but they are not and never will be obligated to not post about ships, kinks, or tropes you dislike just to avoid you seeing them. It's up to you to blacklist words or phrases, block tags, or even block users as needed to avoid seeing content that upsets you.

No one can force you to read anything against your consent. Any content you don't like seeing can be instantly avoided by closing out of the offending post/fic.

You are not owed an online experience free of discomfort.

Nothing that happens in your imagination can ever make you a bad person. Words you write or read about fictional characters will never make you a bad person.

The claim that media consumption influences real-life behavior is intellectually dishonest and serves only to excuse the behavior of real offenders.

Fiction is a safe way to explore horrifying or confusing concepts. Therapists agree that fiction, even (or especially) about taboo topics is a good coping mechanism, especially, but not exclusively, for trauma survivors. Fiction is to adults what play therapy is to children. This doesn't stop being true if the work in question is of a sexual nature.

Sex isn't an inherently worse or better motivation than anything else. A work written to create feelings of arousal isn't dirty, shameful, or in any way less pure than works written to entertain, provoke moral questions, or for other reasons. And worth noting is that multiple purposes can exist in the same story, especially fanfiction.