Just popped in to make sure nobody was answering "yes", damn psychologists need to stick to science fiction.
Edit: I don't mean it's mystical, I mean the details are not scientifically known and probably will not be known for a very long time. When somebody can do a brain scan and tell you that you prefer chocolate or vanilla then we can realistically start looking. Until then there is only the most generalized theories that cannot be called anything more than educated speculation.
That educated speculation would more or less boil down to this: Sexual attraction criteria are subject to deviation at some point between conception and puberty, probably more towards puberty. Reasons unknown. The range of deviation is extremely wide, people are sometimes sexually aroused by shoes. Very common deviations include homosexuality, zoosexuality, (and the one which shall not be named). These are likely more common because they represent a mostly functional sexual attraction system.
Imagine if you will that over millions of years the sexual attraction system was built in layers of adaptation. First it was good enough to want to screw anything that had a hole. As creatures became more mobile and less automatic that became very wasteful. It was filtered by a negation down to things that moved, or smelled a certain way, etc...
Eventually high intelligence started to come on the scene (depending on how you define this it could be Triassic or much later), the whole point of intelligence is to abstract, generalize, and thereby avoid brittle fragile control systems. Instant adaptation.
Every hardcoded instinct is a potential override to intelligence and thus a potential vulnerability. There is no point in being intelligent and then having your brain zone out because you smelled a pheromone.
Thus even sexual functions were integrated into higher brain functions. Pheromones still matter, sensations still matter, but they are only a foundation and not a complete system.
Sexual attraction was generalized and the mechanism of generalization is what is probably failing here. Just as before when the system had to be optimized by cutting out possibilities the generalized attraction seems to form in the subconscious with almost no limitations and then by instinctual rails be focused into what makes babies.
If you think about all the things you could try to fuck, inanimate objects, plants, phantasms of your own imagination; higher mammals we see as peers is pretty close to the intended target. Normies have some component that constrains the sexual attraction from any sexual creature to only humans, its residue is apparently disgust.
Straight normies have a component that constrains even within the same species. Again that seems to leave a residue of disgust, something that is far from apparent today but the historical evidence for it is overwhelming and I don't think something such as what I've been describing just goes away.
On the bright side we can see that with very light indoctrination that disgust can be entirely suppressed to the point where it doesn't really bother almost anyone. This would have seemed an unimaginable state of affairs for a 18th century homosexual, but they would not have had sufficient respect for the power of consistent media, peer pressure, moral teaching, all at a young age. Much as many zoos today don't seem to understand... It can be used to make little nazis but it can also be used to make people who don't want to murder you for sexual deviance.
