Your question starts from a false premise though, that nobody except for the wealthiest can afford to own a house. I'm from the USA, not Canada, so I had to look up the statistics for your country. You're definitely facing a crisis, and if nothing is done, then your statement will probably be true sooner, rather than later, but it's not accurate today. The prices of homes up there are certainly preventative for working class families, but depending on the area there are still middle class citizens buying homes. It would be disastrous for them if their homes - which have traditionally been the one source of financial stability - suddenly plummeted in value.
I totally get your sentiment since we're facing a similar situation down here. Something needs to be done. Ideally that something doesn't completely screw over millions of working class citizens who have made all the right moves, have been disciplined and financially wise, and through no fault of their own find themselves on the shit end of the stick yet again.
I think blocking investors and corporations from buying houses is a good step in the right direction, and probably making them sell the houses they already own too. That alone would open up a lot of inventory and stop the massive appreciation we've seen over the last half decade. That of course carries its own set of challenges though. What do renters do who can't afford to buy a house, or don't want to buy a house, when they suddenly have no more rentals available?
Idk man. I'm glad that I'm not the one who has to sort these problems out. My only point is that I hope they consider the millions of working class citizens who already own homes as they plan their solutions.