On one hand building dedicated dongas without connected ventilation should (almost completely) eliminate transmissions out of quarantine, which is why Howard Springs hasn’t yet had (and is unlikely to have) a breakout. Which should mostly put an end to lockdowns and interstate border closures. Which is what should’ve been done 12 months ago.
However it doesn’t bode well for international travel. Given these centres will be built post vaccine rollout it doesn’t show the government has any confidence in the program establishing a herd immunity. They’ll want to be seen as “been tough on borders” to win votes so little chance current restrictions will change even post vaccine program (whenever that will finish now) for the foreseeable future even post election.