Having a preference isn’t wrong? Some people like hairy people, some don’t, red heads vs blondes, etc. Now we can all argue that internal characteristics are probably better indicators: is this person good? Is this person nice to animals, etc. But there’s nothing wrong with having a preference along the axis of a single attribute.

There's nothing wrong with having preferences. Discrimination gets a bad rap because of it's association with racism, homophobia, etc, but everybody discriminates all the time, every day, typically about incredibly simple stuff. At the end of the day, it's just recognizing differences in people and making decisions based on those differences. Yeah, you shouldn't let something like race or gender impact a decision to hire someone, but you're already discriminating against one gender when selecting romantic partners. (unless you're bisexual and have exactly a 50/50 preference) If you're only attracted to people with athletic builds, you'll be discriminating against tons of people with health conditions. If you're looking for a goth partner, you're discriminating against all the people with happy families. I don't really think discriminating over pheremones is any different.