Factors which can stop housing speculation in Canada

"Therefore, the supply and demand problem that drives housing price up can never be addressed by simply building more homes, because they take too much time and any supply created will be very quickly absorbed by new money flowing into the market."

I really don't see how this is true and the author doesn't provide more evidence for it. If you want to make housing pricing cheaper for renters AND harm foreign investors the best way is to build more apartments. There is, in fact, a limited supply of foreign investors and they are not going to continue to buy into an asset class which is expanding rapidly. Building small apartment buildings can take under a year once approved and a few years tops for massive buildings - which is a very short timeline considering how long housing will be an issue if you don't build.

Of course - this hurts local homeowners which are politically connected - which is why it doesn't actually happen. But, if you don't weigh the goals of local homeowners much higher than local renters then it is pretty clear that building more would create a lot of jobs, a lot of housing, and stabilizing home costs.