Yeah I’m sure incidents are unheard of in other airspace systems....
Don't make excuses for a piss-poor airspace system. Four people are dead in an easily avoidable accident. Unfortunately the complexities of airspace design and systems are beyond a simple explanation to a coroner, a politician or anyone else that makes the decisions to properly administer and regulate an airspace system.
Admit it, you are a 3rd rate airspace admin. You are the pig with lipstick, you look shiny and new to anyone with little knowledge of what goes on behind closed doors. Too lazy, too ignorant to go out into the big wide world and see how a modern, properly resourced 'not for profit' administration keeps the public safe.
It's all well and good to say it's pretty simple to arrange your own separation on a CTAF frequency in IMC. I have been in that holding pattern with 3 others while one is shooting an approach. Of course if you rip VOR's and NDB's out of the ground, where else are you going to go? The nature of the IFR training done in Australia is that VOR's and NDB's are required by those who pay for it.
But you'll come back with, 'no one wants to pay for it' You're on the Kool-Aid, it's paid for many times over.
There are some fairly straight forward solutions, Class E being one of them. Airservices doesn't want a bar of it, Your CEO can't staff the airspace you've got let alone any new classifications. It all fits in nicely with CASA's in-action on this front.