The bill was put up for public comment for less than one business day before being rammed through Parliament. Australia is just sending out one of the horsemen of the infocalypse so that other countries have an excuse to follow suit. Like how our "Assistance And Access" Act was a test run of the UK's "snooper's charter".
This law will just lead to:
1. kids pretending to be adults so they sneak through these filters
2. platforms winding back their (meagre) child safety efforts since "children are banned anyway"
3. everyone being forced to prove their age via e.g. uploading ID (which will inevitably get leaked)