The big problem in Australia is that nobody really in the government wants to do things to make houses more affordable. Anything that would immediately lower house prices would be a disaster for the political party and somewhat for the country. In fact the government has been doing all it can to keep house prices rising further and further.
First by adding a first-home-owners' grant, which just increased the prices of cheaper property, and most recently by allowing people to take money out of their retirement savings to buy a property. All this does is just add more fuel to the real estate market so prices would increase.
The only real way to lower prices would be for a genuine crash to happen, one where the government would be incapable of doing anything to prevent. The other would be to get rid of negative gearing, maybe just for existing property initially, so that people won't leverage up the eyeballs buying more and more investment properties.