It definitely could be, my understanding is that the principle is somewhat like an intrusive thought, in that your brain is running the identification of a sexual intent, and reacting to that. Whether that’s arousing to the person is somewhat secondary, but the body reacts on some level regardless.

I’m not looking it up, but iirc there was a study done a while back where peoples genitals reacted to erotic images regardless of their sexual preferences. Something about how the brain perceives the context, e.g. you can see a naked person without erotic context and might not have any genital reaction at all.