Dating doesn't just mean having sex. If you feel attracted to a person and they say they're trans, it might be a dealbreaker because you know you can't advance the relationship in the way you want OR, at this point you've realised how much you love this person and you're willing to make it work. So many discussions on this topic will condense it down to the genitalia, but I think those are missing some steps. Sex is also called 'making love' for a reason and if you really love a person, it can be intense and great even if the body isn't exactly what you feel attracted too. Again, you have to look at the big picture of actually falling in love with a person and then taking the next steps in the relationship. Simply flat out denying dating a trans person because "not being into the genitalia" definitely sounds to me like being close-minded.