The Egyptians themselves said their founding dynasties were out of Nubia, do you doubt them?
Why would they lie?
Yes the Egyptians would and did lie but I doubt they were doing so when they discussed the early dynasties. They sometimes described Nubians as similar to what we would call sub-saharan Africans and at other times they were clearly not.
The area of the Sudan was mostly what they called Nubia and that was at the time not Black. They used Nubia sort of like we use African. It can mean a lot of different things.
The people you show depicted as having Negroid features are usually, maybe always depicted as slaves or with leopard skins etc. These are clearly not the same people depicted as early rulers.
BTW, I have never seen a picture of Malcolm X with wavy hair.