Is the land in Africa fertile or barren?

Personally, I think it is caused by the lack of a suitable climate and plants that can adapt to the climate. The land in Africa cannot be intuitively said to be fertile or barren, it depends on the region.

For example, the highlands are exposed to wind and rain, and nutrients are washed away. Estuary deltas deposit a large amount of fertile soil. It is said that the land in Africa is barren, but what about the people of the Nile River? The prosperous Egyptian culture was also nurtured by the fertile soil caused by the regular flooding of the fertile Nile River.