The underdevelopment of Africa is/was a deliberate decision of the west that China is undoing.

Smart investors realize China/India's future economic status depends on being able to offset loss of western demand/trade with direct trade with African markets.

This is generally better for the whole planet but not if you have a "zero-sum game" mentality (seems more common in the West than East).

The decisions made by roughly 1800 C.E. industrialists to concentrate development in Northern Europe and the United States can be made on a purely geographic basis. African rivers are generally not navigable to the sea, and to this day the cheapest way of transporting goods is to barge it down the river. The US, on the other hand, has the most extensive network of navigable rivers, with the Mississippi and the connections made to various smaller rivers on the Eastern Seaboard via Chicago, the Great Lakes, and the Hudson.