The pmCO RJ/prop operation at YYZ is pathetic.
(I say that as someone who is based in YYZ)
They run 2-3 flights at a time out of the regional 'barn', where its often difficult to know what is running from what gates, and the procedure on inbounds is to hold everyone on board until ALL the bags are delivered. AA lets people off over in T3, and I've never had to wait more than 3-4 minutes for the door to open, vs. > 30 minutes sometimes on UA.
And its only going to get worse.