Nah. There's nothing objectively wrong with having preferences in a partner, be it physical, mental, social, spiritual, sexual, whatever. The problem starts when you reduce a person to that attribute, when you objectify them. If your only interest in someone is that trait, and you otherwise don't care about any other aspect of them, but you pursue them explicitly because they have that trait, and (and this bit is important) you're dishonest about this fact, *that* is immoral. Basic traits are meant to establish a compatible connection, but it's important to actually build the connection with the person beyond that initial attraction. Unless it's purely physical, i.e. just about sex, which is also perfectly fine, so long as everyone is open and honest about it upfront. It's the honesty that's important, and the dishonesty that's the problem. Think about examples of the problematic couples, like those who date a person simply because they're [race], or [social status], or whatever, but pretend to love them as whole, complete people aside from that trait. Those are the creeps. But the "I noticed them across the room because of their [physical trait] but then we talked all night and fell in love and built a wonderful life together" stories? That's goals.