I feel almost churlish compared to the eloquence of Chief Pedant and tomndebb and others, but I would like to add a couple of things.
First, it is much easier to destroy a culture than to create a new one to replace it.
Second, people whose culture is destroyed and replaced by a slave culture are at a huge disadvantage in the world, for a large number of reasons unrelated to skin color. This disadvantage, being cultural, has lasted far beyond the end of slavery.
Third, it is very difficult to disentangle the complex threads of opportunity, education, culture, work ethic, discrimination, ambition, racism, oppression, and ignorance in the issue of the record of the American Black response to generations of slavery and discrimination.
Fourth, there are very, very few nations in the world where the bogus “White=Good Black=Bad” equation has not held true, to a greater or lesser degree, over much of recorded history. Go figure … we fear those who are different.
Fifth, racism takes a variety of forms, ranging from blatantly overt to very, very subtle. All of the forms, however, have a single aim - to hold the person of color in an inferior position. To varying degrees, these apply from early childhood on, in almost every field of endeavor, in every country that I have ever been in.
Sixth, for a good chunk of fairly recent history, white colonial powers dictated the education, status, and opportunities for a good chunk of the people of color on the planet.
Seventh, black people come from the tropics, which tends to engender different attitudes towards work (especially regarding preparing now for future conditions) than living in a place where if you don’t collect firewood in the summer, you freeze and die. Tropical folks have never heard of the parable of the Ant and the Grasshopper, nor do they have any need for it.
The combination of all of these has affected attitudes and education and opportunities for Black people for millennia. As a result, I see no way to answer the question posed in the OP. There is no black population which has avoided all of those damaging things listed above.
For example, the only country in Africa which was never colonized was Lesotho. I’ve worked there, they live in the highlands, ride horses, and wear Mexican style ponchos, nice folks.
But for the last hundred years or so, it has been mostly a country of women, because the men have been hired away to reside and work in the South African mines … so while their country was not colonized, the men were and for the most part are still all “kaffirs” for 11 months out of the year.
I don’t think there is any country on the planet with a “level playing field” that has actually been level enough, for enough generations, to let us determine the answer to the OP’s question.
w.