Let's be honest. IMO the assumption of Australia being an island was right (as evidenced by the states that made sure their states were islands most notably WA). At this stage WA is clearly the "gold standard" of COVID management, not NSW. NSW, given the numbers it was taking through its "hotels" which never should of been permanent quarantine facilities in any case was not "an island" at all. They arguably were just lucky most of this time, and through hubris of the local people there this was considered good "gold standard" management.

The low tech easy solution for a country like Australia is really better quarantine facilities (i.e. not hotels in the middle of population centers) IMO coupled with a vaccine rollout geared to workers at the quarantine facility (and potentially freight facilities). Its easier to rollout the vaccine and subsequent updates to it for future variants to a smaller number quicker. States in Australia that limited their international intake seem to be doing better than particularly Sydney who were taking the most arrivals. It really isn't an island when your taking the brunt of international arrivals. The fact that it was even working (hotels) for as long as it did shows the effectiveness of a good quarantine strategy. Low tech, simple solutions usually trump high tech solutions that require everyone to participate (problem of the commons).