In my view all the recent lockdowns in Vic, Qld, WA and SA were not required and I said so at they time. Only with NSW with the unkown transmission chains was some level of travel restriction waranted.
As I understand things despite the "roasting" of many things Vic so far in this outbreak, since Oct all outbreaks have been ceased in 7 to 14 days. This one looks to be on track to achieve that as well despite it being the more transmissible strain.
In addition, and I have been flat chat workwise (a welcome change) for the last fortnight and so I may have missed a report or two, but has not every new positive been one of the initial workers or within their first ring? Most if not all of these latter cases have tested positive while in quarantine and no one has been out positive in the community for long lengths of time. There have been no mystery cases so far. No unknown transmission chains. Then the second ring beyond that. While some have been critical about lag of some contact tracing, the numbers to be traced are vast due to the second ring used in Vic which not all states have done of late (ie they will contact less). If so that means that the containment and control system is working and working well.