(i) "Sydney is building a massive oversupply of property...".
But just take a look at what's been happening with dwelling completions since 2006...yikes! It is nonsense to claim that there is an oversupply of property in Sydney.
(ii) "Everyone's stopped having babies due to housing affordability..."
(iii) "Adelaide is going to have a house price boom because it's cheaper than Sydney..."
With no jobs growth at all in evidence, net overseas migration into South Australia is likely to dry up fairly sharpish, while there is already a negative impact of net interstate migration from South Australia aka. a "brain drain" to other states with superior employment opportunities.
I'm not sure how one concocts a property boom out of that.
Demographics Q3 released
Immigration slowing in mining states
In fact, net overseas migration slowed across the board, and this has been particularly the case in the mining states.
On a net basis fewer and fewer people are departing Sydney and Melbourne, where they feel relatively secure in their jobs, which is inarguably adding ever greater pressure to inner suburban property prices in the two largest cities.
New South Wales leads population growth
However, as detailed here recently, jobs growth in the capital cities of Brisbane and Perth has done very well to date to offset declining employment in struggling regional towns and cities, particularly in the resources sector.
The long run data shows how heavily focussed population growth has been upon the four most populous states, and most notably the four capital cities therein.