You pretty much can't compare the definition of "city" or "urban area" in different countries, so that tells you nothing.
I mean, Berlin has 3.7 million people in a city of 890 sq km. Melbourne has about 5 million people in a city of almost 10,000 km. They're incomparable, and so the urban population of Australia and Germany are incomparable. (You can play with the definitions as much as you like but you'll never be able to compare arbitrary Australian and German cities.)
I mean, Berlin has 3.7 million people in a city of 890 sq km. Melbourne has about 5 million people in a city of almost 10,000 km. They're incomparable, and so the urban population of Australia and Germany are incomparable. (You can play with the definitions as much as you like but you'll never be able to compare arbitrary Australian and German cities.)