Doesn't your paper you linked imply it isn't so obvious?

Yeah sure, in the absence of any other data.

If you refuse to acknowledge that people like people similar to themselves, you're not being honest with yourself, let alone me.

What is the systemic problem/problematic behavior that you are trying to solve? You clearly believe that white men are especially discriminatory towards other groups, which isn't crazy, although I disagree. But are you so naive to think that if we replaced the powerful white men with powerful hispanic women (or any other combination of race and gender), racial and gender-based discrimination would suddenly end? I'm just pointing out the inconvenient truth that the system would still be biased and unfair, just with different winners and losers.

In my view, the fact that some white men are biased for or against certain groups is completely insignificant and irrelevant to solving the problems that society faces today. It's the fundamental structure of the economic and political system that naturally results in the few individuals at the top of the hierarchy expressing a large degree of control and domination over the rest of the society.