I guess I'm missing the humanitarian aspect; facts don't exist in a vacuum and the "question of fact" we're considering has already cut reality into an absurd slice of state space. Given the world we live in, I would like to see some solidarity with a discriminated group before we dive into answering an ill-posed question willy-nilly.

It seems to me that there are so many foundational questions we'd need to consider first.

What is intelligence? Who gets to define intelligence? Could we possibly measure intelligence in an accurate non-culturally-skewed way? If we could define intelligence, what would its dimension be (i.e., how many parameters would we need to specify it)?

Should the multi-dimensional measure of intelligence be assigned according to a person's peak potential, or their average potential? If measures of peak potential verses range of potential vary independently from person to person, how would we compare two people? In general, how do we compare two multi-dimensional distributions that don't have the same shape?

What is the value of asking about the result due to genetics in particular given that it is practically impossible to separate genetic and environmental effects? Consider:

(i) without the effects of cultural selection maintaining the different populations, genetic meanings of 'black' and 'white' would quickly become meaningless

(ii) even if someone imagined they were controlling for genetics by looking at cross-racial adoptions, a lot of cultural selection has already occurred in the biological mother's choice of partner and with environmental effects during gestation (there is already a large health gap between mothers of each race, and if the child was given up for adoption, the care during gestation may be an influencing factor)

(iii) Genetics is a result of environmental selection anyway, and it might be non-sensical to compare distributions that are not in equilibrium.

Given that the question is so complex and ill-posed you have to ask why the question is being asked. What exactly would be irrational about not wanting to glibly admit (socially) if one group has a higher IQ than another group, if it was possible to know it? Is it irrational to not want to entertain a racist agenda? Is it irrational to find it quite troubling that someone you're talking to would want to discuss the issue of whether one race is inferior to another race, for any reason? I understand that we can't avoid 'truth' just because it is troubling, but what kind of 'truth' are we pursuing here? I don't think we're qualified to answer this last set of questions. We're reductionists, and need to keep in mind that some issues are so complex there's no way to currently address them without being greedy.