How big of an part do pheromones play in homo- and bisexuality?

I'm sure most anons are familiar with trap-posting, both 2D and 3D. People often say shit like "I'm not gay for fapping to traps (men)". However when you see a trap on the screen it's a blank slate right? There are no pheromones present.

Would people who are turned on by traps aka "straights" be turned off if they experienced male pheromones instead of nothing? If they really are straight this should be the case and that means humans are pretty bisexual when it comes to visual stimuli