At last Friday\’s Cato luncheon featuring Gregory Clark, Clark emphasized that settled agriculture is a much more arduous lifestyle than hunter-gathering (he said if he had to be tossed back in time prior to 1800 he would rather be placed in a hunter-gatherer society than in an agricultural one). To get the same amount of food, the civilized farmer has to work a much longer day.
When a modern factory becomes available, it\’s not such a great stretch for a farmer to adapt. But for a hunter-gatherer, the long work day and monotonous nature of labor are really alien. Thus, it was much easier for Japan or China to eventually industrialize than it has been for Australian aboriginals or for Africans.
As long as we restrict that to Africans with a hunter gatherer lifestyle (and thus not the Bantu tribes and many others who are indeed farmers) then yes, that might be part of it.