Do you think that mistaking Africa as a country reinforces the thought that Africa is a monolithic culture?

Yes. People would never mistake Europe or Asia as being a single country because they realize that Europeans are a diverse group of people just as they know that Asia is full of people of diverse ethnicities and cultures. Yet people seem to think of Africa that is mostly a barren, wild land filled with exotic animals and blacks who look the same, speak the same language, share the same culture and history when this is far from the truth. This is due to the stereotypes reinforced in the media, schools and other places about Africa also due to the lack of media exposure and education on the diversity and richness of African cultures, languages, people and history.