If this is the case, I suspect some type of interim Bus solution is best instead of waiting a couple of decades to start anything.
I think Long Branch (LE GO) - Sherway - Kipling (MI GO + Line B) - Renforth (Line E) - T3 - T1 - Woodbine (KI GO) - Humber (Line F). and maybe a couple of other stops too.
Google Maps tells me it's 80 minutes for 37 km. add 10 minutes for stops and that's 25 km/h average speed. A bit of roadwork for bus jump lanes would be needed, so it's not free - but it's relatively cheap and relatively fast to get into service. Some stops (Woodbine KI GO and Renforth Line E) can be omitted at first.
Note, Line B = Line 2, Line E = Line 5, Line F = Line 6.
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