These silly semantic games always seem to stray from reality pretty fast. When you say that feminine qualities are "socially and arbitrarily defined" you seem to think that simply acknowledging this (even if we assume that you're right) takes the functional validity away from these definitions. Heterosexual men are not interested in other men who have managed to create a convincing illusion of being a woman. A straight guy finding a trap attractive at face value (which is exceptionally rare anyways, given that 95+% of traps are pretty blatant) does not make the trap a woman. It all relies on deception, as the vast majority of the time a regular guy will, immediately upon finding out that they have been tricked will cease to behave as though they are interacting with a woman, because they now know they are not doing so. They will cease to fundamentally think of the person in front of them as a woman, because they are not a woman. There of course is a chance that they are not straight, and do not care, and will roll their eyes and go for it anyways, but this relies on the man having homosexual tendencies. The whole notion that choosing what traits you express somehow changes fundamentally what you are is absurd to me, as if it's somehow invalid to be a feminine guy or a masculine girl. Want to be a femboy and be submissive and get fucked in the ass? Great! Do it! Want to be a woman who lifts weights enough to overpower and sexually dominate your choice of partner? Great! Do it! But it doesn't LITERALLY make you a woman or a man, no matter how you LARP. Additionally, anime traps are a laughably bad representation of real life traps given that the artist can just draw a girl and slap a dick on it, where the girl has fully developed female breasts, a woman's bone structure, facial features, hips, lack of an adam's apple/hair/muscle, etc. It its totally contradictory with real life.