The first mid-air involving an RPT aircraft in ‘G’ in Australia will test the comfy CASA/Air Services/ATSB/Operator status quo against the political target level of safety. It will scare the hell out of a lot of punters. My guess is that CASA won’t get away with saying: “It’s the one-in-1XX million movement accident that is a risk that we’re always taking.”
I still don't think an occurrence like this will change anything. Australia will go to extraordinary lengths to avoid building 'permanent' infrastructure, like towers. ASA doesn't want to cop the bills for their construction or staffing costs and they have allies in government who know that it's their budget allocations that fund it in the end. What happens are ridiculous airspace concepts (see Ballina) that can be dropped once the traffic 'normalises.' (if that will ever happen).
When a politicians job is genuinely on the line, if they're ever accountable, thats when things will change i.e. things will never change.