We'll try everything, it seems, other than holding parents accountable for what their children consume. In the United States, you can get in trouble if you recklessly leave around or provide alcohol/guns/cigarettes for a minor to start using, yet somehow, the same social responsibility seems thrown out the window for parents and the web. Yes, children are clever - I was one once. If you want to actually protect child…
But let's assume the majority of parents can actually do this. The problem with social media is not an individual one! We've fallen into a Nash Equilibrium, a game theory trap where we all defect and use our phones. If you don't have a phone or social media nowadays you will have much more trouble socializing than those who do, even though everyone would be better off if nobody used phones. As a teenager, you don't want to be the only one without a phone or social media. And so I truly do think the only solution is with higher level coordination.
Now, it's possible that the government isn't the right organization to enforce this coordination. Unfortunately, we don't really have any other forms of community that work for this. People already get mad at HOA's for making them trim their lawn; imagine an HOA for blocking social media! I do think the idea of a community doing this would be great though, assuming (obviously) that it was easy to move on and out of, as well as local. This would also help adults!
So to be honest, I don't think parents have the individual power to fix this, even with their kids.