A bunch of Youtube videos? Anyone can do that. The first video the guy is talking about the findings of South American "Negroid" findings. Those "Negroids" were NOT Africans, because the remain which is named "Naia" was said to carry Haplogroup D1 which is not even found in Africans, but instead found in Siberia(where the ancestors of Native Americans are from).
Naia's 12,000-Year-Old Skeleton Holds Map to Ancient American Genes
Basically Paleao-Americans would have resembled Africans early on as MOST Eurasians did also including Europeans. Does not mean they were genetically African.
As for the videos about Van Sertima, I read his work and again he NEVER says the Olmecs were African themselves.
Black People : - Ivan Van Sertima: "Reply to My Critics"
So again Van Sertima NEVER said Africans were the fore founders of the Olmec civilization, but only that they influenced one another. And even so there is very little strong evidence to suggest Nile Valley civilizations traveled to the Americas. There have been no physical remains, Ancient Egyptians who were known for writing down people they met and yet no mention of indigenous Americans, no pre-American items found in Egypt or vice versa,etc.
Now Muslim West Africans reaching the Americas? That's another story which actually has a good argument backed behind it. We actually HAVE historical records of an attempt for that!
As for the video titled, "Black people of Asia". "Black" indigenous people in Asia? So. They're still not African...
The one of African origins of Asians is just silly and all it is just picture spamming. The DNA of Asians Negritos and non-Negritos show them distant from Africans anyway.
The video about the Tamils and Dravidians is also even sillier and the video uploader is citing Clyde Winters who is a hack and not taken serious in acedemia. This is the same guy that tries to argue that their is a connection between Niger-Congo and Dravidian... Yet claim Berber is not African.
And don't even dare say he's not taken serious because he's black. Because while academia in the early days did not agree with Diop, they actually respected him and he is known as advancing opening to Africanist thinking in the field he is in, where as Winters is just a joke.
More importantly you can find Winters on Egyptsearch where no one takes him seriously.
Both Dravidians and Tamils carry clades that are distant from both Africans and Europeans...
Like I said Afrocentrism has a positive part but then sometimes it transmutate into radicalism where it tries to become like Eurocentrism.