Egypt isn't evolving, they are kind stable and struggling to show their maximum performance while Cameroon gameplay is improving from a game to another without fluctuations.
It will shock you that Egypt will play in the finals and also take the trophy. You may not like their pattern of play and you think they are a struggling side but you have to know that they are playing to instruction to conserve energy. That is what matters. Not what the Nigerian team did by winning all their three group matches and then lost miserably to Tunisia.
It can be possible for Egypt to win the trophy, they have what it takes to win a trophy, so it won't be a surprise to me. With the performance of their last match I think Egypt is doing better that when the tournament started.