They didn't and they haven't.
It's more nudge nudge wink wink age restriction theatre than 1984 total surveillance.
The onus is on platforms (Facebook, Youtube, et al) to adhere to the request to restrict minors.
https://www.esafety.gov.au/about-us/industry-regulation/soci...
https://theconversation.com/details-on-how-australias-social...
https://www.abc.net.au/news/2025-07-30/teen-social-media-ban...
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