I don't really understand the comparison here. Lots of people are very frustrated with slow zones or other limitations on line 1. They don't suggest rebuilding line 1 because that is obviously not the solution to the problem, maintenance and modernization is, and that is clearly on the long-term...

Sure, you're right that the SRT was decommissioned for unplanned reasons. But my point is that when the capacity constraints on the tramway portion inevitably start to show decommissioning old infrastructure won't be the end of the world. Especially on Eglinton which is already mostly a subway...

Not to dwell on hypotheticals but I don't think it's that unlikely that eastern grade separation could take place eventually, considering the density that's being built along the corridor. Plus we did just shut down the SRT and put in a bus replacement service while the SSE gets built so there...