OK, so the big threat in future is the supposed sell off by baby boomers as they downsize. Question, where is the reasearch that supports this contention? Baby boomers will often want their existing space for ther family to visit, to holiday, or just because it's their home. A survey might help clarify this contention!
What is causing house prices to rise is not a lack of listings, ie buyers waiting to sell, waiting for better prices etc, these sellers are not out there, period.It is a shortage of houses being built.This is caused in large part by the paranoia councils have in allowing land to be zoned be developed into sections.Showing almost a religious zeal for high density living, council live in a land of denial, people do not want to and will not choose to live in on tiny sections or in small apartments.This is not Europe or Asia, we do not have a large population or a lack of land.As in all consumer items if there is a shortage of supply prices will rise.Nothing will change, housing will just become more unaffordable while councils constrain supply.