To people from other countries, but especially Americans, this part is important:

The mother of a trans teenager mounted a legal challenge which was heard in the Supreme Court in Brisbane – arguing the directive was unlawful because the correct processes had not been followed.

In his written decision, Justice Callaghan said the proceedings were not concerned with the merits of the directive.

"They are concerned solely with the legal requirements that attend any decision of this nature, irrespective of the subject matter," he said.

Courts in Australia are almost never political activists in the way they are in America. They apply the law as it is actually written. In this case, the Health Minister has the power to give directives like this, but is legally required to consult first. I don't believe the Minister would need to side with the preponderance of evidence in such a consultation, but the process must be followed. This is a big win for now, but if he's determined, it's very possible for him to undergo that consultation and reinstate the ban.

IANAL, but I suspect that if consultation was undertaken, even a small vocal minority would be enough weight for the Minister to be permitted to make this directive, and it would probably require near-unanimity against the decision for the directive to be unlawful.