It is nonsense. But thinking it's okay for kids to be able to go outside and do what they want, but oh no the internet is dangerous and we need IDs is even more ridiculous, quite frankly.
If you don't want kids using social media, set up a network filter. But if you want to have mandatory ID for social media to "protect kids", but you have no trouble letting your kid go outside and get up to who knows what (they're absolutely going to be browsing the internet on their "cool friend's" computer and doing devilish things like saying naughty words on reddit), then I think anyone who really believes that needs to post their ID as proof. Because it's a very contradictory and inorganic thought process.
There are many laws regulating adults behavior outside. Outside is safer then online too.