Here's why racial preferences are wrong.

Firstly, they're racist. People try to think and believe they aren't bad but that actually hurt the opposing person's feelings all over something they can't help.
" I hear it all too often: “I’m not racist, but I just wouldn’t date [insert race/ethnicity].”

If you have to start a sentence with a clarification that you’re not racist, that’s a pretty good indicator that you need to reevaluate whatever you’re about to say."
I quoted that because I found it from another site and I agree with it. Also saying "but" doesn't make your case any better. 
Racial preferences aren't really preferences. I like apples over oranges is a preference. Using race isn't a preference.
Racial preferences are wrong both ways. Whether it's my own race not wanting to date any other person because of their race or another race not wanting to date any other race because of their race.
You're leaving people out of things they can't not help. You're rejecting or refusing to date someone over their fucking skin color. That's like judging them, hardcore. You'd be friends with a black girl but you'd never date one? I don't think any black girl would be dumb enough to even want to be friends with someone like you. I wouldn't even feel comfortable being friends with you whether I'd like you or not because to be honest, it sounds like there is something deeper than just the preference. For example, it sounds like you don't really want to date black women because they're too loud???? Which is stereotyping which you are wrong for.
Refusing to date someone because of their race sounds like you won't date someone because they're fat or you won't date someone because they were born mentally disabled. It's something they were born with and can not help. And they should not feel guilty or down upon themselves because you don't want to date them because of their race.
"Oh, I'm just not attracted to this (insert race)." That's not attraction and you sound stupid. You can be attracted to (a lot of people do this) people regardless of their race. Stop misusing the word attraction.
The person you could be dating could have some of the blood (of the race you don't want to date) in them. Then what? You're going to leave the person you so claimed you loved because they have blood in them fro a race you don't want to date. Seems like you never really loved them to begin with. That you dumped them or divorced them because they had something in them you did or do not like.
Or what if you don't even know the entire time? You can never be sure. And what the hell does someone's race have to do with not liking them or wanting to date them? You know people of any color or race or ethnicity can be beautiful so why even lie? Their race or stereotypes about/against them have nothing to do with their personality. Yeah they could be a black girl but the sweetest/nicest quietest person in the world but yet you claim (because of stereotypes) that all black girls are loud (which is false).
Step outside of your stereotypes and look deeper for why you won't date someone cause of their race and stop calling it preference because you don't have a clue what preferences mean. There, I'm done.