Sounds awful but I don't think it would change much. People usually don't like to talk about their fetishes. Though it would make finding porn difficult and there would be various versions of different fetishes. Like there would be feet necrophiliacs as offshoots of necrophiliacs.
Which wouldn't be too difficult if your fetish isn't fucked up. If someone had an apron fetish then they should hook up with someone who has a cooking/baking fetish.