As LH says, it's a historical artifact.

Sure, it shows blacks as less intelligent/educated, because that was the European-imperial view back then. Post-WWII, I can also find you a whole bunch of war books and films showing Germans as psycho Nazis, because that was the general view of the US/UK folk who would be reading/watching them.

In other works: As an apologist for imperialism, Kipling generally shows the people of India in a good light, but also makes it clear that the whites are in charge and the natives are grateful for the whites running the place. "Porgy and Bess" was hugely daring for 1935, but today (and even by the 50s) it was seen as grossly stereotyped. And Harper Lee calls black Americans "Negroes" in "To kill a mockingbird", which isa deeply un-PC word today.

Graham.