Australia did well with Travel Restriction for travellers from China.
This bought precious time for preparation.
Unfortunately the horse had bolted. Covid 19 infection had moved to a different phase with many new cases outside China and outbreaks in many parts of the world.
If only all the other countries had also restricted travel from China from the start, this Covid 19 would have been largely contained by now. The short term economic gain had now turned very painful.
For Australia, travel restriction won't work so well any more with so many places involved.
Is Australia Prepared in the event of a local outbreak?
At this point, medically it's a no. It takes time to reorganise workforce, acquire resources and build capacity. It's getting better though.
Society side, well, seeing how some brawled over toilet paper, the country is doomed should there be local outbreaks.