Yes, like most other countries, Australia does a reasonable job of enforcing its immigration laws. As you note, Australia actually isn't so geographically isolated that this is a trivial problem; and just like other forms of high-stakes law enforcement, some implementation details look unpleasant, especially when one ignores the downsides of the alternatives.
But Australia is ultimately near the top when it comes to how much sustainable opportunity it offers per capita to foreigners (and nonwhite foreigners in particular, despite past "White Australia" history, if you care about that). It is reasonable to try to do better, but that's pretty much impossible for the US until the people can again trust the government to adequately enforce whatever laws are ultimately decided on.
(I think Canada is the country in the best position to try to do significantly better today. And not coincidentally, it is a country I plausibly may emigrate to if things unravel further in the US.)
But Australia is ultimately near the top when it comes to how much sustainable opportunity it offers per capita to foreigners (and nonwhite foreigners in particular, despite past "White Australia" history, if you care about that). It is reasonable to try to do better, but that's pretty much impossible for the US until the people can again trust the government to adequately enforce whatever laws are ultimately decided on.
(I think Canada is the country in the best position to try to do significantly better today. And not coincidentally, it is a country I plausibly may emigrate to if things unravel further in the US.)