That's fine and it would be nice, however I fear any Provincial involvment will come with strings attached, specifically reuiqring these lines to be built in the most unproductive way. Look at the Eglinton West extension, there is zero justification for that line to be underground yet the powers that be insist it must be for reason I don't think anyone will ever understand. Whats to stop the Province from doing this to the EELRT and Waterfront lines and inflating both the price and scope of the projects? I don't like the Cities or Provinces unhealthy obsession with everything needing to be underground, and I have no doubt that any cooperation from the Province will come with these ludicrous strings attached.
As long as the Province doesn't have to fund them substantially i doubt they'll care. Keep in mind a good portion of the Crosstown on the east side is already sadly neutered into having poor grade separation. There is really no reason to push for full separation then what we are already designing East and there really is political points to earned compared to the central Scarborough connections.
I think the support for the EELRT from both residents and institutions is underestimated. The central SELRT and SLRT support was fragile to say the least, this line is completely different and will continue to be pursued.