I don't know about the above. To me, given that Mississauga has already built out to its borders, and Brampton is nearing that soon (they're starting to get up to Mayfield Road), the GTA seems sprawly to me. And in Mississauga's case, the only possible way to continue population growth is to build up now.
I'd consider some residential towers as sprawl too. I believe sprawl is defined as "the unrestricted growth in many urban areas of housing, commercial development, and roads over large expanses of land, with little concern for urban planning.", and I feel that some residential towers are being built with little regard to the surroundings. For example, there is a proposal to build a tall (can't remember the exact number of floors) tower at the corner of Yonge and Bernard in RH, which doesn't seem like a great idea due to the surrounding infrastructure probably being unable to support that. There's also a tower proposal on a vacant lot next to Alexander Mackenzie HS at Yonge/Major Mack, which again, does not seem like a wise place to build such a tower.