Australia, NZ, and Iceland were very very successful on their own terms, having zero or near zero cases for > 1 year and normal social and economic activity.When Australia chose its course, we did not know which of these were correct.
Now we do.
We don’t know the reason why one country is successful. It might simply be that they had a mild virus similar to the wuhan coronavirus previously and that gave them immunity.
It might be something else.
Or maybe because they are not letting in unscreened "refugees" and illegal aliens and transporting them all over the country.