First, from your link:
>Our data also provide evidence for shared ancestry among geographically diverse hunter-gatherer populations (Khoesan speakers and Pygmies).
Would we say that pygmies, being considered black, would be likely to make it into the NBA?
Second, can we guarantee that people who self identify black, would agree that the definition of someone else's "blackness" is legitimate? Whose definition do we "choose" to then move ahead with "and these sorts of black people are more likely to get into the NBA?" Given that it's not well agreed upon (is Obama black? Steph Curry? Not as cut and dry as you might assume. Are they "black enough" to have NBA advantage?)
Third, based on your tallness: why draw the line as 6'2"? There are shorter players that were Great. So, how do you deal with (relatively frequent) exceptions? "Tall people are more likely to get into the NBA, except when theyre short but grew up next to a court" ? And the tall People that aren't good at basketball? "Tall People are good at basketball except when they're not" ? And when they're too tall to the point that it's detrimental to their health and can't even play basketball?
Fourth, arbitrary. Exactly. It is arbitrary, and thus I argue scientifically impossible to have a rational discussion about blackness and its influence on likelihood to enter the NBA. Or, rather, develop an effective predictor algorithm based on genes alone.
We could have interesting sociological conversations about basketball courts in predominantly black neighborhoods, black NBA stars inspiring black kids, self-propagating cultural memes about blackness and basketball skills, etc. But we won't get any really good information that allows us to say something like "black people are better at basketball" to where it will be true.
Regarding pygmies, they are a different cluster from the highly homogenous cluster of Niger Cordofian from which current African American population in America descends. From the article I cited: "High levels of heterogeneous ancestry (i.e., multiple cluster assignments) were observed innearly all African individuals, with the exception of western and central African Niger-Kordofanian speakers (medium orange), who are relatively homogeneous at large K values(Fig. 5C and fig. S15).)".
I see you are also a bit disingineous if you dont think there is a high correlation between athletic abilities and genetics. Gimme a competent geneticist, 200 hundred genomes of 15 years old boys: 100 African Americans and 100 Guatemalans, shortest dudes in the Americas. I am pretty confident that I can pick 2 teams of 5 kids just by their genome and pick the correct winner of a basketball game between them with high probability. Yeah I cannot predict individuals outcome(yet) but population wise I think it is not a crazy stretch.
On the other hand I see your point that there is no crystal clear boundary between any human group, but if you take that position you have to be consistent with it. What I mean is that I assume you are not happy with an universal definition of black (I can understand and even agree with that). But then you are forced to admit the concept of White privilege is vague too. Same reasoning. You could say "White" is a cultural concept, but I could say the same regarding "Black" so we are back to part 1.
Again I suspect we have more points in common that differences regarding this topic, I just wanted to put out there some considerations.
As all parts of culture, the concept of white privilege is extremely vague, and I imagine white Milwaukee trailer park residents would be a bit offended to be lectured about their privilege. Hence why I would prefer we spend our time focusing more on socioeconomic factors of humanity rather than genetics - it just seems more useful.
I may return to edit this if I have time today but if not thank you for this discussion.