That’s another point, even if it were physically possible and enjoyable for both parties, the social differences in customs would be a big problem.
Though I guess if we had multi species colleges there’d be lots of experimenting and one night stands and not as many long term relationships.
Of course the romantic fantasy of two outcasts of their own cultures finding love with each other is also possible.
So my short answer remains, “It would happen but not be widespread”.
Maybe it’d have the side benefit of getting all the human racists to stop hating each other and team up against aliens.
Racist father sees daughter come home with human of different race, maybe he thinks “At least he’s human!”