The restrictions clearly do not benefit Australians.
Negative excess deaths benefit Australians, it means fewer Australians die. Living instead of dying is a benefit.
People are even allowed to kill in self defense to avoid death. Why shouldn't governments be allowed to restrict freedoms if they achieve more people surviving ?
Closing restaurants is milder than killing enemies. Yet killing enemies is considered reasonable to avoid enemies killing you or your neighbours. It is not considered reasonable when the danger the enemies pose is just hypothetical.
Closing restaurants usually won't save lifes, and then it is not justified, but in the case of COVID-19 it did.
You are a little like damned if you do damned if you don't.
If there were positive excess deaths you'd say the measures were ineffective and abusive. If the measures work and excess deaths are negative, you say the measures weren't needed and were abusive.
If you can only be happy when the average deaths stay flat you'll likely to be deceived no matter what policy in place.
To assess the Australian policy we'd need much more data. Was people dying of COVID or of forest fires ? Does the correlation hold when looking at subplaces or subtimes?
Do we have the lists of measures and time in force and does it bear a relation to excess deaths ? What happend in all those parallel universes where there wasn't COVID or there weren't restrictions ?
Is my crystal ball pink or black ?