I honestly think something like that is going to be as much or more of a harm for the person making/using it. When the world is just flooded with fake images I think we’re gonna get jaded by them very quickly and it will be just another form of (really fucked up) cyberbullying.
For the people making them the harm is more insidious. They’re likely to be doing it in secret (because weird/immoral sex stuff) and isolating themselves, and we end up in a weird Futurama Lucy Liu-Bot situation with even more social isolation and further declining mental health.