Africa have always had good depth in terms of decent teams, Nigeria and Cameroon didn't even qualify for example. Anyone that had any sort of African football knowledge or anyone that watched Afcon would know that the increase in the number of African teams in the world cup wouldn't lower the quality. (I don't think the same can be said about the AFC and CONCACAF).
The issue with African football is there's a lot of solid teams but not a lot of teams capable of winning the world cup which is why they lag behind Europe and South America in terms of hype.