We have now surpassed the daily new case figures that VIC experienced last year. If NSW daily numbers begin a decline now it could be 2 months before it's under control.
And I think there will be lockdowns after 80%. The trouble seems to be the 20% who DON'T want to get vaccinated or obey restrictions will end up choking our health system when a large proportion of them require ICU and/or ventilators. See what's happening in some USA states and in Israel.
So, yes, lockdowns after 80% vaccinated to protect our health system(s).
Of course, there are no absolutes - there are still cases of severe symptoms in those with two vaccine doses, but I'm sure they will be in the minority compared to the anti-vax/freedom/conspiracy/religious nutters who will get infected.
/rant