China already has such legislation. They have placed restrictions on social media and internet use for children, and they censor content on these platforms.

Personally, I'm against government intervention for this sort of thing. I prefer government to be constrained to securing my liberties, rather than restricting my behavior "for my own good".

As a parent, I talk to my kids about social media like I talk to them about junk food. I want them to recognize that it's bad for them - it's addictive, and provides short term pleasure that results in long term misery. Avoiding it, or making good decisions about how you interact with it, is a personal responsibility issue.