From December 10, children aged 16 and younger will be kicked off platforms including Facebook, Instagram, Snapchat, TikTok, YouTube, Threads and X.
The government is stepping up its advertising campaign to build awareness of the ban, one month out from its start date.
"The great thing about this, I think, is more so than anything I've ever seen, this is a grassroots movement that's come from the bottom up," Anthony Albanese told Nova radio on Monday.Â
"It particularly has come from parents who have gone through tragic circumstances, lost their young son or daughter, and channelled that trauma and grief into trying to make sure that it doesn't happen to others."
One of the issues driving the ban was that young people don't have the capacity to discern what is real and what is not before the age of 16, Mr Albanese said.
"It is just about giving them back their childhood. That is as simple as that, and we want people to be protected," he said.
But opposition communication spokeswoman Melissa McIntosh claimed the ban was "set up to fail", saying it was unclear on details like whether platforms could compel users to verify their age using digital identification.
"The details really matter, and the minister should be focused on those first and foremost," she said.
The government announced earlier in November the list of platforms had expanded to capture the forum website Reddit and live-streaming platform Kick.
Discord, Twitch and popular gaming site Roblox won't be affected by the ban, but Communications Minister Anika Wells said the list would be fluid meaning more platforms could be added.
Many were unprepared and did not know which platforms were banned, said Mrs McIntosh, adding the government "has simply not provided enough time for families, schools and kids to be ready".
More than 200,000 Australians have visited the eSafety website since an education campaign launched three weeks ago, attracting almost 100,000 page views weekly, compared to fewer than 10,000 previously.
Ms Wells said the numbers were heartening, with the information to drive meaningful conversations about the significant change.
"Now is the time for people with under-16s in their lives to start having conversations about what the new law means for them, and talk through any concerns or worries," she said.
"Young people who expect to have their accounts deactivated from 10 December can also take steps to prepare and make sure they stay connected to the people and things they love, including by backing up content and photos and exploring other ways to keep in touch."
The onus for complying with the ban rests with tech giants to "detect and deactivate or remove" accounts from underage users.
Companies that fail to comply could be fined up to $49.5 million.
Denmark has announced it will follow Australia with a social media ban for children younger than 15 but has yet to settle on how and when it will be enforced.
The Scandinavian country has a national electronic ID system open to Danish citizens aged 13 and older.