I agree that racism is not just history yet, slavery, for example, was not that long time ago and the perception of blacks as slaves has largely influenced how people perceive blacks, maybe so far as in today (and also because slavery and the post-discrimination led to serious consequences such as the current disadvantage of blacks)
However, as you said, these things happen in an unconscious level that it is very hard to control, if not impossible. And if I owe to anyone to broaden my horizons by defying those "basic" attractions that I have is to Myself, and Not to You (as in the the Minority You). If i do that for You I'll be acting from pity, I don't see how that can generate attraction. That's because attraction is indeed selfish, and that's the only way it can be.
But look, in the end, we have to give time to time. Yes, if there is an unconscious bias towards attractions to different races that - might - be associated with conscious discrimination that was made in the past. But it'll only fade away with time.
Also, from what I realize, most people have preferences on race that are far from binding, and in the end, don't you rather stick with someone that likes you for who you are more than for how much they are attracted to you?
It does scare me that this is a matter of discussion, because the only reason that it is it's because there is:
1. An apparent bias in sexual attraction to ethnicies
2. A counter-culture to that apparent bias that tries to scare people from minorities into fuck amongst themselves (by excluding them from "the group" if they do not - like the author is being!)
I'd say that's quite sad, wouldn't you?
I say: Fuck everyone else's opinion on to whom I am sexually attracted to. Let my dick decide that. Is it not enough I have to deal with the fact that some people can't accepted that my dick prefers men, I also have to deal with people who can't accept that my dick prefers exotic or familiar?
Of course, for those whose dick only gets erect to a certain ethnicity, that can be quite limiting, but it is up to them to decide whether they want to test those boundaries or not.