I can't see any other reason for blocking the canal than to stop warship movement.
To me, the Egyptian pilot is most likely involved. Those ships must have navigation and sounding electronics up the wazoo, and it works, considering the amount of traffic and how many groundings have occurred. Not sure, but language in the control room must be English, like air traffic, so she could converse with the course hackers in Arabic while ignoring the ship's crew screaming at her in English as the alarms went off.
Guessing Arabic interests want warship access stopped, and commercial damage is a by-product, not the motive.