the AUKUS subs are attack subs. Who will they attack? Attacking China would be about as stupid as anyone could get.
Assuming you can't use attack subs for defence is about as stupid as anyone could get.
Japan wanted to attack Australia and we were weak as water but they didn't think they could achieve a direct attack so chose to do so using Port Moresby as a staging point. The long journey around the tip of PNG was a problem but their invasion force was intercepted in the Coral Sea. The rest is history.
Eighty years changes a lot, but not geography. An aggressive China would still have to sail around PNG. "Attack" subs could "defend" in the ocean and the RAAF could stage out of Scherger and Townsville. The aim is not to defeat China in a war but to make the juice not worth the squeeze of attacking us. If we defend against the first wave, the US will be there soon after.
