I mean the "Edmonton-Calgary corridor," which is certainly more spread out than the vancouver metro but is still a recognized connected urban region, at over 3 million people, is also not an insignificant chunk of Canada.

I'm pretty sure you can find well over 11.5 million peoples'-worth of regions to pile up into a counterexample for what the post was saying. I think the point is that "across canada" is a broad brush to use for this.

Oh yeah, it's a big chunk of the people, but the claim was "While you might be correct looking at other markets, you would be surprised how average it is for Canadian Housing prices across Canada. It is impossible to not to earn a minimum of 20 % on any Real Estate transaction withing a year." - that's not the case across Canada, only specific sections.