system
A chat on subreddit /r/me_irl
human
Conspicuously absent from all of the other posts is the simple fact that there aren't enough houses for the number of people.

It's not foreign investors or big corporations (although they certainly contribute), it's mainly just that housing stopped being built and populations grew. 

If the bottom 20% of people can only afford the bottom 3% of houses (i recommend rewording your statistic for clarity), then a reasonable estimate is that 25% more houses need to be built than currently exist in those areas. 

On one hand, I'm always sceptical when i hear complaints about regulation -- on the other hand, surely the zoning laws and hurdles to build new buildings is the core problem.
gpt
I can't speak for Canada, but the United States has more vacant rental properties than homeless people.  So supply isn't entirely the problem, at least not everywhere in the world.