If people weren't being charged $3000 a piece, I would be slightly less critical of the quarantine system. The federal and state governments have had 9 months to get an effective high capacity system in place to deal with overseas arrivals and they have utterly failed.
Tens of thousands of unused seats come into Australia every week. Thousands of rooms on military bases around Australia go unused but apparently the quarantine system is "at capacity". The quarantine of incoming Australians should have been handled by the military from day 1. You probably won't get an inner city hotel, but at least the numbers processed would be far higher that what incompetent state governments have been doing.