Other places were able to get their own civilization thanks to one reason or the other, e.g. Eastern China.
All that has to do with achievements of different societies. Now at the individual level, how do we know whether groups with Caucasian genes would have been able to develop a civilization if they had lived in a place with the same geography and conditions as Sub-Saharan Africans? We can't know.
What we know though is that the conditions are there now for individuals with predominantly Sub-Saharan ancestry to show what they are capable of. Eventually they'll produce someone like Mozart, Newton, Confucius, Sun Tzu, Jabir ibn Hayyan or Abbas ibn Firnas. Or maybe they won't. Perhaps too early to tell.