It's the parents who are wrong.

Parents shouldn't allow their kids to use social media until they can handle it. Some kids don't have issues, whereas others end up experiencing severe depression largely as a result of too much or too little social media exposure. Parents should be the ones responsible here, both for deciding the age and for culpability if they knowingly contribute to problems by either intentionally over or under exposing their children to social media.

But at no point should the government be deciding things like ages, because enforcement would necessitate privacy violations of either the parents (if they need to allow an underage account) of the children. Screw that, let the parents decide and hold them accountable for any abuse.