Someone else in one of these canal threads said that Egypt charges slightly less than it would cost to sail around Africa. If that's true, that Egypt is probably capturing around as much value as is possible from the canal.
You'd be wrong there! They actually have a rebate system[0] based on a number of factors including origin and destination. Basically, they try to make it so that its always cheaper to go through the canal, rather than sail around.
[0] https://www.wilhelmsen.com/ships-agency/suez-canal/suez-cana...