It is now becoming obvious that after Australia led the United States and other leading aviation countries by six years in the ADS-B mandate that there are now business jets which are flying non-ADS-B compliant and are being forced by Airservices Australia Air Traffic Controllers to fly at flight 290 or below in the non-radar airspace. Already I have heard that one plane was forced into very bad weather.
Whilst I see your point, the mandate for ADS-B has been out there for a while, and there is a process to give yourself more time to become compliant. If a pilot of a bizjet can't follow that process, that's negligence on their part. Whilst it is expensive (I think around 50K?) and it does take the plane out of service, if you can afford to own and maintain a biz jet, you can afford to upgrade to ADS-B. They aren't Commodores.
If I was a professional controller I would not like to be told that I had to force business jets to low levels( up to $1000 per hour extra fuel cost as well as the WX worries) unless there was a good reason for it.
About 400lbs/hr difference at 280 v say 410. At the current Shell price for A1, 182kg is about $350 an hour. And that's on what are probably less efficient turbines than on newer jets.
Planes fly at 280 and below all over Australia, Dick. I don't see the problem.