You're overlooking the long history of sex work in most human civilizations. Fair enough if you morally disagree with it and wish it didn't exist but it's existent and the existence of people who provide and consume it is about as normal as it gets.
If you accept that sex work will always exist in some capacity then there are reasonable arguments that the existence of OnlyFans is a good thing, as the OnlyFans model of sex work is in many ways much better than traditional models for both the sex workers and the consumers. There are of course arguments against that too, but saying sex work is fundamentally immoral and thus OnlyFans should be stopped is naive and more importantly unhelpful when it comes to reducing the potential harm sex work can cause.
I wouldn't say that sex work is fundamentally immoral, but using deception to manipulate people into giving you money is hard to defend. Of course this occurs in many other industries, too.
If you accept that sex work will always exist in some capacity then there are reasonable arguments that the existence of OnlyFans is a good thing, as the OnlyFans model of sex work is in many ways much better than traditional models for both the sex workers and the consumers. There are of course arguments against that too, but saying sex work is fundamentally immoral and thus OnlyFans should be stopped is naive and more importantly unhelpful when it comes to reducing the potential harm sex work can cause.