There are two development models. One is the Chinese way where you build it and they will come. We laugh at their ghost cities but i'm not really sure why sometimes. The alternative is the Indian model where you cram as much into existing infrastructure as possible. We seem to be doing the latter.
The real problem at the moment is the horse has bolted. If we had an honest conversation two decades ago about growth and actually planned for it,it might have been manageable. However, right now, we are majorly behind. House prices are astronomical which hurts retail and thus tax tax, everyone is geared to the eyeballs and this affects the domestic consumption. There have been practically no new developments of commerce centres anywhere which means growth is concentrated in Syd/Melb and the worse is the escalating costs of infrastructure are now critical. You can't build roads, rail and schools cost effectively anymore because there was no land reservation policy and no real coordination of high density developments. So yeah the guv stuffed it. But the way forward is not to maintain the population growth levels, that's effectively trying to dig yourself out of a hole.