This piece isn't very useful, for three reasons. First, the foreign buyer tax was never suggested as a silver bullet, but it was supposed to slow the market way down from 30 percent year over year price increases. It has certainly cooled the market. Second, just because prices aren't way down doesn't mean it is useless: if it hadn't been introduced, then prices might be even higher. That's the relevant counterfactual, and the piece doesn't even acknowledge the point. It took some of the speculative demand out of the market, so it is hard to see how it could NOT have helped. Lastly, the piece doesn't mention two big interventions after the tax to prop up the market: the government loans to first time buyers and the loophole creation in the foreign buyer tax. Both moves suggested that the government wasn't going to allow prices to fall, and this spurred "domestic" speculative demand again - remember, they were introduced when the market was ice cold in December and January.