Because progressive governments all over the world dropped the ball too. Didn't hear anyone attributing Australia's success to the conservative government when the country was being heralded as a miracle just a few months ago.
The fact is the Australian federation model has an odd separation of responsibilities which makes this challenge uniquely difficult for Australia.
The state governments haven't failed on health though? The federal government explicitly declined to let the states run the vaccination program in the way that they wanted and instead went GP-first (GPs being beholden effectively to the feds).
This is a nothing statement. The state based health services have generally been very well run, with the exception of contact tracing in Victoria during 2020.
The federal health responsibilities (vaccines, quarantine and PPE provisioning) have all been spectacular failures.