Not sure this generational divide argument holds water much. The children of boomers, who grew up in relatively nice houses with backyards, similarly want nice houses. Increasing supply in an urban planning context involves increasing high density dwellings in the inner city. This is a hard pill to swallow for adults who remember playing cricket in the backyard with their Dad or whatever idyllic notion they are left with from their wonderful childhoods (not a joke, Australian kids have great childhoods by any metric). The boomer parents also want the same thing for their adult children, and help fund the acquisition. As boomers die off and the wealth passes to their kids, they will invariably spend it on houses (or second houses) as well.
I also think different cities in Austrlia have differnet issues. Adelaide has a very old demographic and little migration, and has the problem that their health care costs are going to greatly exceed their revenue. Melbourne has had too much migration, which tends to just make the economy look fine but causes a lot of strain on infrastructure. Melbourne and Sydney also suffer from being gravity wells for migration, so that people don't leave for better paying work elsewhere or cheaper housing. They choose to suffer underemployment in very competitive and saturated labour markets with unaffordable housing. I include myself here.
Housing affordability is not going to improve. There is no way prices are going to correct by the 30% - 40% in desirable places to live to get into the realm of affordability. Increasing urban density is neither attractive to people nor likely to happen. It's done and dusted. The only thing to hope for is that the rate of change will slow down, and wages will improve so that at some point in 30 years time affordability will be better. That means there will be a generation of people who don't own their homes, and the comparison to the previous generation will be highly unfavourable. Being an elderly renter is a greatly inferior experience, and the government outlay for housing the elderly will simply increase more and more.
The 'solution' to my mind is to strongly encourage people to move to places with more affordable housing and good living conditions.