But in all seriousness, i think Africans (and other oldworlders) have a very local view of their people. A black person from Mozambique really feels no more allegiance or admiration towards that cameroonian mathematician than they do to dangote as a nigerian industrialist. They are all foreign to him. Hell, africans within the same country are hesitant to claim the accomplishments of rival ethnic groups. For example , an english speaking cameroinian would probably spit on that mathematician breh's face based on their current conflict with french speaking cameroonians.
I think the only exception is maybe world cup season, when a kenyan, ghanain, and nigerian will claim random africans on a soccer team(think france in last world cup).
you can compare it to how a white canadian couldnt give a damn about the accomplishments of a white italian scientist or an irish silicon valley billionaire because of his own nationality/ethnic differences. Race is irrelevant.
America is a strange place in that it forces a global view of race , in a way which is unatural in other places. You see it elsewhere in the US where loosely related people are arbitrarily grouped together for ideological goals. Think of how southern white conservatives went half way accross the world to congratulate the hungarian victor orban. Or think of how a random nonsense grouping like "latinx" groups hispanics that have nothing in common, besides spanish.