I don't think that's what Cartier meant, I think he meant Africans don't see blackness the same way African Americans do, we don't see it because we're ALL black and therefore we can't use it to beat others down, it's a non factor. Instead of race we are separated by ethnic tribes and social classes, whereas African Americans are in "one pot" for lack of a better term.
It's like if Shaniqua was reading AAs using nigger reads against Trina and 'em.... it'll be like well your a nigger too.
Yemi reading Nigerians is a bit different because, Nigerians are separated by huge ethic tribes and different social classes, it's a different context, different set of dynamic, values and cultural norms, a lot of Africans are elitist, and that's what she's guilty of here if anything.