The problem doesn’t lie in differentiating the obvious extremes: the problem is in moderating everything that falls between them; in determining which kind of sexual fantasies are “allowed,” and under what conditions, and how to make those judgements consistently.
Here’s the thing: when we conjure up a sexual fantasy for masturbatory purposes, it’s designed to pop like a soap bubble once we come. The very act of fantasising about anything means putting a barrier between the realities of the situation and the reasons we enjoy it in the moment, and that’s especially true of sex. What we want in fantasies, what we enjoy in fantasies, very seldom maps perfectly to what we want in real life, which is why it’s so very dangerous to start judging people’s real morality on the basis of what they wank to. That’s not to say there’s no correlation between morality and what gets people off – there are plenty of racist fetishes, for instance – or that we shouldn’t interrogate our preferences. What I’m saying is that there isn’t a clear binary of Good and Bad in the majority of cases, and acting like there is will get you in trouble.
A very common example: in real life, communicating about sex can be difficult or embarrassing, even though it’s necessary, so people fantasise about perfect sex that happens without communication. Sometimes, this is because both parties are so perfectly in sync that words aren’t necessary, but other times, the fantasy is of one party taking control because they ‘know’ what the other person wants. In real life, that sort of behaviour is generally a red flag – but in fiction, the fantasy is explicitly a what if: in this case, what if they actually did know?
Another example: in real life, people enjoy sexual roleplay, where consenting partners act out non-consensual or dangerous scenarios. In fiction, the ‘consent’ aspect of engaging with those same fantasies is inherent in the act of deciding to read them in the first place; the characters don’t need a safeword, because the only real sexual participant is the reader, who has complete control over their immersion in the story. These are the kinds of stories that tend to make people the most uncomfortable, because it often looks like the narrative is romanticising toxic or abusive dynamics by giving sexy descriptions to terrible things. But this is precisely what tags are for, which is one very strong argument in favour of fanfic being better at consent than many traditionally published stories: the very act of tagging content means that the reader knows that the author knows the thing they’re writing is bad in real life, but that it exists here for the reader to indulge in as a fantasy, whether sexual or otherwise, just as they would with a roleplay. By contrast, when you encounter similar dynamics in a published book, you have no idea whether the writer knows the thing they’re describing is Bad unless they explicitly say so in the narrative, which makes a lot of readers – myself included – uncomfortable about engaging with it.
Overwhelmingly, sex written as pure pornography doesn’t strive for perfect realism, because the whole point is to focus on a specific definition of arousal or pleasure detached from any negative real-world consequences. This is just as true of happy, loving sex depicted between consensual adults, where nobody ever gets a cramp or has an inconvenient period or tears the first time they try anal, as anything darker or more disturbing.
So, yeah – there is absolutely written content on line that I personally find gross and bad and disturbing, but I genuinely don’t believe there’s a safe, reliable mechanism for excluding it that won’t massively fuck over a whole bunch of other stuff in the process. If you want to pay for a website to try and walk that line – and you’d have to pay; there’d be no way to ensure good moderation otherwise – then that’s your call, but I don’t believe you get to decide that for everyone else, no matter how honourable your motives.