Because of this there are two industries that are big winners: construction and the direct resources sector. EVeryone else--including software--are losers. So you might earn A$100-150K (base) as a senior (5-10+ years professional experience) software engineer in a capital city but you will have an extraordinarily high cost of living.
To put this in comparison, my nephew at 17, was a deckhand on a tugboat in a mining port making $120K+. Now that he has a license to captain a vessel up to 25 metres I believe he's rapidly approaching if not exceeding $200K.
Now this isn't without expenses either. A crappy home in a mining town can probably put you back $1000/week or more in rent (20 years ago they couldn't give these houses away at $50,000).
He's not a special example either. Those who did apprenticeships (eg electricians, plumbers, fitters and turners) are particularly well-off. Australia is highly regulated when it comes to these jobs. If you say you're a licensed electrician and you're not you can go to jail. The only way to get licensed is to do a 4 year apprenticeship.
The plus side of this is that the standard for Australian tradesmen, at least in my experience, is exceptionally high. The UK is essentially unregulated here (by comparison) and if you're in the UK, hiring a licensed Australian tradesman is really your best bet if you want quality work.
Now, software engineers are on the high end of the salary scale for those who must (or generally do) go to university. You could easily end up in other disciplines only making $50,000 a year. Trust me when I tell you that in Australia this is a pretty low standard of living now unless you were lucky enough to have bought a house 10+ years ago.
So what you're seeing in this post is nothing new to Australia and it's even more pronounced in Australia.
I actually think this is an economically structural problem. Building a new house now (both my brothers-in-law are in construction) costs about $1500-2000 per square meter (for single storey, add 50% for two-storey). New apartments in West Perth now sell for up to $10,000+ per square meter. This is insanely high and well beyond local living standards (for all but a few).
Anyway, picking up one of these trades in Australia at least instead of going to university has been lucrative for many years and shows no signs of abating.