The ground stations are not the whole problem.
Airservices don't appear to have put in the hard work and money to have the ADSB returns shown in the terminal facilities in Sydney and Canberra. Others report Willy Approach also can't display ADSB returns.
What a con. GA has to pay over $30 million and it doesn't even work in busy terminal airspace where risk is higher.
And yes, lots would support the US ADSB requirement for VFR if Australia allowed the freedoms of the US system for VFR. But that's unlikely to happen .