They’ll open. Just not by Christmas. More likely by about this time next year and in a staged way. Whether demand returns quickly is another thing entirely.
I expect by this time next year, Victoria will be in its 10th lockdown, the feds will still be negotiating with the states over dedicated quarantine facilities, the premiers will continue keeping the population in fear and under emergency powers, vaccinations will have stubbornly stalled at around 60%, not enough to reach herd immunity and far too risky to open the borders.