Home routers have something called parental controls which can help parents block certain websites and platforms at the home network level.
This together with parenting and education of ones children can help, all without sacrificing and giving away our privacy to third party corporations.
At a regional and country level I would suggest a government funded public service similar to a library to index the internet. Similar to how books are classified by age and genres.
These lists can be provided within each home router by defult for easy selection, or made easily available for upload by parents or users into existing routers.
These government funded publicly curated list can help parents offloaded a little of the "curration effort". This can then simply be a setting or toggle in the router setup, applying the proper age appropriate whitelist and blocking everything else that is not on the "approved list". The setup can even help parents classify specific devices on the home network as "child owned" so the list only works for those devices.
This would be the most "privacy respectful" option IMO over things like "age verification" or any other alternatives being suggested by corporate tech firms at the moment.
The tech for this is already here, where we are lacking is:
- A government funded public curation effort.
- Goverment funded public education campaigns and education programs.
- A incentive for router manufacturers to make home router setup as simply and straight forward for non-tech or non power users.
As for power users and tech literate individuals, public lists curated by individuals online already exist. For example Pihole and Adguard lists, these help people block and whitelist websites at the home network level.