No one is stopping people from going home, they just have to travel by the legislated paths, as they didnt return by road before the hard border came into affect.
I know you think the ruling is unfair, but withholding emergency medical treatment in the nearest hospital in retaliation seems really petty to me. The people waiting in Wadonga for an alternative resolution to the one currently on offer (i.e flying into ACT) lives aren't at immediate risk,. But driving 3 hours to a Sydney hospital in a emergency would cost lives, vs 10 mins to Canberra.
ACT residents can go home, SA and WA residents coming from Vic arent even being allowed to return to their homes except for some extremely limited cases. Qld has the same fly-in rule for anyone coming from Vic or NSW (be they resident or exempt visitor). But SA, NSW and Qld arent refusing to treat border town residents at their nearest hospital. Maybe think on that.