Mostly because of the specialization. The Jewish is specialized in ER (and super innovative at it too!). So they make the most sense to compare for ER. Anyone waiting at the Royal Vic should be their for one of their specialties (like EPRAC and chest). The children’s hospital (part of the Glen complex which includes the Royal Vic) has extremely low ER wait times. And so it should. Cannibalization of children’s ressources to supply the Vic’s ER defeats the purpose of specialization.
All this to say: the Royal Vic should maintain high wait times, to incentive prospective patients to go to hospitals that specialize in ER and have better wait time.
Montréal has enough hospitals that you can think of it like each department in a normal hospital having its own hospital. Sure they different depts/hospitals can do things outside their scope, but it’s not ideal.