Part of the issue here is that at the local level, much of Australia is basically a Third World economy and has been for years.
WA - Dig it up and ship it out. Classic Third World stuff.
Qld - Same as WA with the addition of tourism. Again that's Third World stuff.
NT - Again, not much more than natural resource exploitation one way or another.
Tas - Mixed in terms of actual activity but government policy has, with the exception of a brief period early this decade, focused heavily on natural resource extraction - that's Third World stuff.
SA - Was a developed economy as such but has fallen in a heap due to the impacts of events in other states plus lack of scale locally.
Which leaves NSW and Vic as the only states that could really be considered as "advanced economies" in terms of actual activity and are managing to do it with enough scale to be useful. I didn't mention ACT since it's a government city in terms of economics and probably always will be. Necessary yes, but it will never likely become a net income earner for Australia.
We have a lot of issues in WA and Qld especially as the mining boom winds down. But that was always inevitable and there's no point blaming unions, environmentalists or anyone else for that outcome, it never could have lasted and so it didn't. The question isn't why has mining investment fallen in a heap? The question is how did we end up with such high reliance upon it in the first place? Economically at least, WA is up there with the likes of Saudi Arabia in terms of a total lack of economic sustainability. Once the iron or oil is gone, that's it, game over. Completely unsustainable and the proverbial blind Freddy could see what's going to happen in the long term.
It's a fairly safe bet that 35 years from now, coal mining in Qld will be an irrelevant activity economically and LNG will be at the end of the line too. Iron ore in WA will be well on the way to being stuffed by then too. Better start planning now for what's inevitable.
PS - no offence intended to anyone living in any particular state. I'm just calling it as I see it - digging stuff up or cutting it down and loading it onto ships with little if any processing is classic Third World stuff. We can't expect to sustain a high standard of living with that approach.