The foreigner tax was a cynical exercise by Christy Clark to make it look like she's doing something. The provincial and federal governments can  do more. 

For starters, the province could restrict the number of houses a non-citizen can buy to one.  How about implementing laws against flipping? How about a surtax on properties owned by foreigners assessed at over $1 million? How about allowing foreigners to buy property in Canada only if Canadians have reciprocal rights (China has restrictions)? How about eliminating  pre-sold housing overseas? How about insisting house sales be registered with RevCan and buyers disclose their source of income? 

As was the case recently with the Westbank condos in West Van and townhouses in my area,  increased supply and density doesn't mean anything if your starting price is completely out of range for anyone except wealthy foreigners who can afford to buy one or several condos and townhouses.  In some cases, they sit empty for speculation purposes.