I'm sure the TTC has several problems, but one problem with building ANY sort of transit infrastructure in or around Toronto is the land cost. Quite simply put, it costs a hell of a lot more money to buy a corridor of land in Toronto than it does in Montreal or Vancouver. This is true not just of subways but also of roadways.
Again, I bring up the example of the 407 -- total cost to taxpayers was in excess of $100 billion when you include the land purchases. Considering that it will NEVER be anything but a highway that is not land that can be resold later, unless inconceivably someone rips up the highway and builds housing on it. Not going to happen--so it was a straight cost of $100 billion.
Those who say the gas taxes pay for the roads like to pick the spending figures from years in which there were no major land purchases. When you look at the total cost of building a road, including the cost of purchasing the land it's on, it's fucking huge.
Subways are a little less expensive because they can tunnel under, but generally there's still a lot of land purchasing involved, and if you put the subway through an area where it's really needed--meaning a built up and dense area--it's fucking expensive.
What these other cities did better than Toronto was to purchase the transit land once upon a time when it was less developed and cheap.
Toronto pushed off building transit for decades, failed to buy the required land when it was affordable, and the result now is that we can barely afford to build a single station a year, due to the costs.