If you think all that about social media, smartphones, etc, which I think too, why would you need the State to make YOU disallow YOUR children from using those devices?
If you believe those things, you are already doing it, in a much more fine-tuned way than any bureaucrat can possibly put into a law, suited to your exact preferences and your children's personalities and developmental stage.
But of course, most likely your concern is what OTHER people do. But other people's children are none of your business.