They also assume he's guilty whilst simultaneously claiming they have no evidence to demonstrate to a court that guilt. That's contrary to the Universal Declaration of Human Rights (Art.11).
Also...
> Enquiries showed that he was contacting these females
What are these mysterious enquiries? Why not follow up on those? If one or more of those victims was willing to give access to their devices/accounts they'd get the evidence they needed anyway.
I know this is a rhetorical question, but the answer is that the whole "THINK OF THE CHILDREN!" angle is a façade. The real reason to implement any of this is to gain more power over the populace by making meaningful resistance of the government harder.
Do not fool yourself: Australia is on a slippery slope towards a heinous future, and ignoring the UNDHR is one of the key steps it is taking towards that event horizon. It has never given a damn about the rights of Aborigines and Torres Strait Islanders, by way of example ..