There is SO much of that around the GTA though, there will long persist single family houses next to high density housing.
The area being shown in those photos, however, is mostly industrial, as the GTA also depends on a lot of horizontal buildings to function, mostly warehousing of course, and therefore industrial space is also at very low vacancy rates. It's just not realistic to expect that the whole area is going to become dense in the vertical sense anytime soon.
Was it Peter Ustinov who called Toronto "Vienna surrounded by Houston"? A little out of date now, that should probably be 'Manhattan surrounded by Vienna surrounded by Houston', point being Houston's still out there, and will be, to most extents, for the foreseeable future.
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