What would be the impetus for the extension of the Bloor line into Mississauga (the only place it could go after a station here)? We already have one subway line about to cross the city boundary which I'm sure will prove to be a terrible allocation of resources.
Crossing the border on the western side would serve way more people than Vaughan ever will.
Anyway, I'll even take a one stop extension to Honeydale/Cloverdale. Although at this rate it'll be another 40 years after that for another 1-stop extension to Sherway.