You are setting up an enormous straw man. When you say people like the GP say:
> We will always be just as hateful and prejudiced as the worst of us are now.
That is emphatically not what the GP is saying. The problem is not the ideal that race should not matter, it's that history does not go away, or more generally we can not build the ideal world from first principles.
Those with privilege often wish it was as simple as simply being "color-blind", then everything would be fair, right? Wrong. Because even if no white person harbored racist thoughts of any kind, we are still saddled with racist institutions and wealth distribution. Even if police magically became completely egalitarian, black people would still suffer the brunt of police brutality, because they still live in the poorest areas where there is the most crime.
The bottom line is that, if you are a white male (which I am), then you really and truly should be listening and not proclaiming any strong opinion or solution, because privilege is a blind, and so you really are not qualified to have an opinion about what should be done about sexism or racism. I feel like this is especially onerous for geeks (again, like me) who value their ability to reason, but understand that your (my) feelings being hurt is much less of an indignity than most black people face on a regular basis. Don't get defensive and try to prove how non-racist you are. Instead just take a deep breath and realize that this country forcibly imported 10 million African slaves. Despite how uncomfortable that makes a lot of people, there really is no way for that legacy to ever be erased.