This is not a problem that is unique to Toronto and Vancouver. Every major city, New York, London, Singapore, Tokyo etc. has the same problem....
The only reason the government is considering getting involved is because some middle-class Canadians are saying "Twenty years ago we could have bought a house in High Park and paid it off in less than thirty years, now we can't. Do something about it." ... If they want to live in the Toronto or Vancouver markets they need to downsize or look to less desirable neighbourhoods. While it may make individual home buyers unhappy - from a societal point-of-view I don't think either of those are a necessarily bad things.
Excuse the [...] but wanted shorten the quote. The problem with this is that rising property prices, at a certain point, lead to residents being forced to live far from where they work, which is the precise opposite of current planning policy calling for complete communities, and people living within walking/cycling distance of work.
Look at London. I've copied a link below to property listings in Northwest London. This area is easily an hour from Central London by transit, yet you're looking at a bare minimum of
£425,000 for a pretty rough townhouse, and more like 800k on average. Even
£425,000 is unaffordable for most professionals even in their 30's. You can find cheaper in Essex... but it's Essex.
http://goo.gl/T45Dnn
As a consequence, people are moving further into the surrounding areas, even as far as Birmingham, which is completely nuts, and the government are building high speed commuter trains into London. I can assure you that the average London commute, although by train, is still an hour plus each way. This is the way TO is heading, with people moving to Hamilton, Oshawa, Barrie, etc. and commuting by GO. Instead of being stuck in traffic on the 401 they're stuck on a train.
Left unchecked this situation will only get worse. The income level where you are priced out of Greater London is much higher than in Toronto. If Toronto continues to head in this direction a lot of people who are thrilled about Toronto becoming an international city on the same level as London, Tokyo, etc. will change their tune very quickly.