The ironic thing is Australia really only got it when their zero COVID policies weren't taken seriously enough by its weakest actor who was more into "opening up". For people who don't know Australian politics it was the NSW state.
They avoided COVID delta for months (6+) despite locking all incoming arrivals in shared air hotel quarantine systems and workers coming into the quarantine zone day in and day out (i.e. not taking quarantine seriously quarantine). Some Australian states who had better border control policies were able to keep COVID out indefinitely (e.g. WA, QLD, TAS, SA, etc).
Knowing some people who live in WA, despite overseas travel restrictions, life is pretty much pre-2019. Clubs are open, schools are running, no masks, nothing. They are thankful for zero COVID policies - the biggest one being border control and for some areas dedicated, but well resourced, quarantine facilities (NT). Only recently did NT get cases, and it didn't come internationally, but from the NSW outbreak. It's a concern since the indigenous population there typically have less health facilities.
Of course it is much easier to do this in Australia than the US or UK for a variety of reasons. Europe definitely can't do this IMO - land borders aren't strong enough.
Compare Australia vs UK.