Australia has decent health care.
However, when I travel to another country, I get travel health insurance.
It hasn't been required in any country I've visited so far, but I choose to get travel health insurance for the sake of my own bank account. I have had to use it once and was very glad I had it.
But in 2020 ... travel is restricted to our own countries and in my case to one island in my country. No need for travel health insurance.