TempoTCu,
Maybe you are looking in the wrong place, there is lots of aviation outside of three relatively small airline groups that "call Australia home".
One example, known to me, because I gave him his first (part time) job with a brand new CPL.
Age mid-thirties, a tradesman with a family.
Gained the CPL with a local aeroclub flying school.
First job flying single engine.
Got a CIR, gained a job with a local operator, flying various C-310/320, 402 etc.
Got himself to the US, did the usual ATR/multi/ IR etc., and went looking ---- by this stage the biggest he had flown was DC-3/C-47.
To cut a long story short, within ten years he was a wide body Captain for a major middle eastern carrier ---- and there are more opportunities out there now than ever, because the aviation industry is so much bigger.
BUT, as many have correctly told you, age is very much against you in the small puddle (the statistical rounding error) that is Australian aviation.
Tootle pip!!