>>382764you said it yourself, africa was largely iron age. trade with locals was possible (and much trade of gold, ivory, slaves did go on) but limited by local technology. direct extraction turned out over time to be the more lucrative option though more difficult as well, and it was not only the difficulty that delayed colonization, but also the fact that colonization didn't really
need to expand quickly until well into the 19th century when economic competition picked up and the financial sector grew.