Even the trains have been automated, which I assume has been historically difficult only because of unions and safety regulations. A bit easier to pull off in the remote outback I suspect.
This doesn’t seem very plausible to me. You are proposing that there could have been an alternate universe where, for example, instead of sending iron ire to China for steel production, Australia could have become the steel producer. This has many assumptions - firstly, that China would buy Australian steel as opposed to finding another ore producer and doing what they do now anyway. You also assume that this would be a good business in Australia. Quite possibly, the economics don’t play out due to energy/labour costs.
You're far more correct in that China would far rather buy the iron ore and coal from Australia and make steel in China.
Why? Social stability, and the security of the party. Even if it's less efficient to import the ore and coal, the steelworks keeps people employed, particularly young men who might otherwise grow restive.
Isn't that true of almost everything humans do? When I get a tank of gas, I'm basically paying to have a bigger problem in the future. I do so because it solves a problem I have in the present.