I do really wish it had more actual subway lines (and not dedicated streetcar lanes, etc.). But the Canadian municipal governments are neither powerful nor rich, unlike many of the other large cities listed, despite being a quite prosperous and growing city. A lot depends on the provincial government.

Also, it is incredibly lame that there is not a subway to the airport.

However, the maximum 5 min waiting time for a subway (and 2-3 min during rush hour) is very nice, and a huge contrast with, say, the Paris subway, where I think I waited 15 minutes for a subway once late at night. But really, with so few lines, you need that frequency for a 5 million person metropolitan area.