By any international standard, the line would have been built as LRT. No city would think of wasting 1 Billion dollars to move 50,000 riders 5km. If I remember correctly, the EA for the Sheppard subway did not even include LRT as an alternative.
You need to get out more. First of all, there are dozens of subway extension of that length and that ridership (or lower) being built around the world. I lived in Munich for a bit, so the Messestadt and OEZ extensions come instantly to mind. Berlin is building the U5/U55 extension. As I've mentioned, the L train in New York had a lower ridership than Sheppard when Sheppard opened. It's also three times the length.
Secondly, you remember incorrectly. Network 2011 studied subway, BRT, and LRT in detail. They recommended BRT with provisions for upgrade to LRT on Eglinton, and subway on Sheppard.
You'll definitely hear complaints when you tell them they should cancel fully funded lines to start over again. Any sane person will realize just how silly it is to do so. Not to mention cancelling lines that are actually reaching more people than one short line to STC.
This is one of the most blatant logical fallacies of the LRT planning (along with, of course, the inelastic demand numbers). What does "reaching" mean? It's all well and good if the purpose of these lines is to be able to look out your window and see an LRT line (or to put a streetcar in every ward, as Councillor de Baeremaeker said), but if you're actually trying to move people places, the most important thing is for the line to actually serve real travel patterns. How many people in Morningside Heights actually want to go down to Kingston Road? How many people by Rouge Park actually want to go to Fairview Mall? How many people at Jane and Finch actually want to go to Jane and Eglinton? Most of these lines deliberately bypass established hubs like Scarborough Centre because it's a mall (ew! ick!) despite the fact that it's by far the biggest destination in Scarborough. Trips can also include more than one mode. For example, a person riding from Malvern to Downtown will now have two Transit City routes in their neighbourhood. They're not likely to ride either of them. As Adam Giambrone said, the Sheppard LRT will be too slow for people going all the way downtown. The same is certainly true for the Morningside line. The best way to give people all over north, northeast, and east Scarborough a faster, more reliable, and more comfortable ride is to replace the RT with a subway. Yes, the subway might not be in front of their door, but it will benefit far more people.
As for some anticipated public anger, I suggest you head out to Scarborough and ask that question yourself to riders on the Mezzanine of Kennedy station. Ask them if they want LRT now or a subway to STC in a decade. I will bet money on that response. Ditto for the same question to riders at Don Mills.
The key is that people actually understand what LRT is. To listen to the fanboys and city councillors, it's this magical technology that can do anything for anyone everywhere. If people actually understood that it's basically Spadina or St. Clair with longer vehicles, lower frequencies than their existing bus, and at the absolute best about 10% travel time savings, I can guarantee what their answer would be. I can just hear the blustering "But! But! It will be
different!" now, but that's a pretty accurate description of the plans we've seen. I've heard nothing--
nothing--from anyone at the TTC that suggests it will be any different from St. Clair other than POP and occasionally less frequent stops.
You'll definitely hear complaints when you tell them they should cancel fully funded lines to start over again. Any sane person will realize just how silly it is to do so. Not to mention cancelling lines that are actually reaching more people than one short line to STC.
Oh come on. You'd push for cancelling fully-funded subway lines in a heartbeat if you thought it would lead to a streetcar some time down the road.