There’s a 3rd explanation: fetishes aren’t inborn, but they’re not instilled by porn either. Instead, they develop through a complex interaction of psychological, developmental, neurological, and cultural factors.
One theory is that, if a person repeatedly experiences sexual arousal in the presence of a specific object or situation (even coincidentally), the brain may begin to link that stimulus with arousal (classical conditioning). Or if the experience isn’t repeated but it is intense, it can become imprinted as erotically significant. In both cases, the fetish can be considered “latent” in the sense that it existed prior to one’s encounter with porn related to that fetish. Porn simply revealed what was already there (and showed the viewer there are others out there like them, too!).
So-called “normal” sexual behavior is just the median of millions of data points. There is not one person who fits that median in all respects. Even if you can’t find a partner who finds your specific fetish “appealing”, there are plenty of women out there who won’t specifically judge you for it either. Failing that, just enjoy the fetish in your own mind and don’t divulge it to your partner. You’re entitled to an inner life, after all.
Just as we have a biological imperative to procreate, we also have one to eat. But I’d disqualify any potential partner who thought less of me for liking tacos. Again, as long as one’s fetish doesn’t harm others, why should sex be any different?
