Autralia simply DOES NOT NEED low level ADSB
Have you ever heard of "VFR stuck on top of cloud" or "VFR in cloud"?
One of, if not the most, scariest events a controller can encounter... a very afraid and very lost pilot in a very dangerous situation. Out in the GAFA... ADS-B coverage... supervisor gets the call, looks at his screen and finds the aircraft in seconds... unique hexadecimal code = instant identification... reports from other aircraft and ground stations to find a decent hole in the OVC... vectors to the hole and... every cent spent on, and saved by, installing ADS-B is justified.
But... hang-on a minute... VFR on top of OVC only ever happens in the J-curve.. within RADAR coverage... doesn't it?