Why is north africa considered a region that is separated from the rest of the african continent?

There are certain reasons for why North Africa may not be considered "African" in the same sense as the rest of the African continent. One such reason is geographical - that the Sahara Desert separates most of North Africa from that of the rest of the Continent as well as dense jungles and rainforests making travel into inner Africa difficult. Also, North Africa is positioned along the Mediterranean Sea which was a commercial and traveling hub for most of the western world throughout human history. This results in constant contact with civilizations such as Rome, Greece, Saudi Arabia, Egypt, Ottomans, Spanish, etc. that made North Africa part of a different world than what the rest of Africa was experiencing during history. For these reasons, North Africa had enjoyed a different exposure to cultures, possibilities, and commerce that the majority of the African continent was not able to.