Doubtful.
We’re attracted to and aroused by certain things. If you’re not attracted to someone, what they do sexually will hardly arouse you. For ‘straight’ people to say they are completely straight but are attracted to and aroused by gay porn, that’s a blatant lie. There’s got to be some sort of attraction the viewer sees in the person or object that’s doing the sexual act in order for him/her to get aroused.
Example: a 100% hetero man would likely be attracted to and aroused by women rubbing lotion on her boobs. He would NOT be attracted to, thus not AROUSED by, another man rubbing lotion on his chest. If he is, then there’s some bisexuality in him.