Okay, but there is also large swathes of unimportant desert in Egypt and Sudan... And you'll notice that I opted not to compress that area anyway as it was more a problem of where the political boundaries were placed.We have not established that, the observation has been made that Egypt is wide but that it is too wide is interpretation. As I suggested above, Egypt is deliberately wide both in this map and the current map because the Nile is an actually important area of the map that many civs interact with (Egypt, Greece, Rome, Byzantium, Arabia, Turkey) so adequate space needs to be given to it to reflect that. The Nile is both more relevant than the Sahara at whose expense it was expanded and than Senegal/Cameroon or whatever place's expansion would be justified by its size.
I will contend that these areas are very historically important. Western Africa were some of the first colonial outposts of European empires as they sought slaves to build their colonial empires in the New World and beyond. The Portuguese colonised West Africa before Angola. Not to mention the numerous vibrant indigenous civilisations that were there for a time unfortunately underrepresented by one civ, Mandinka, and hordes of aimless Native Pombos. It is no chance that Europeans did not (heavily) colonise Africa first. African civilisations were able to hold their territory and opted instead to engage in slave trade while the European civs were kept to the coast (but they were there none the less).
As far as giving space for different civs interacting with the region
How many civs interact with Egypt at any given time?
Ancient: Egypt, Assyria
Classical: Persia, Greece, Rome
Middle Ages: Byzantium, Arabia
Medieval Ages: Mamluks, Ottomons
Colonial: Ottomons
Industrial: Ottomons, France (kinda), England
How many civs interact with West Africa at once?
Early Colonial: Spain, Portugal + African civs
Mid Colonial: Spain, Portugal, England, France + African civs
Late Colonial: Portugal, Netherlands, England, France, Spain + African civs
Industrial: Portugal, Netherlands, England, France, Spain, America, Germany