That's very different from schools banning use of phone during school hours. And, no, your role as parent is not to blindly follow the herd if you think it is not good. That's certainly true for smartphones and, again, there is parental control if/when you get your children a smartphone.

You can only bring a horse to water, as the saying goes...

My cynical take is that social media are a convenient tool for government to justify more identification and control. ID cards, digital IDs, age verification systems, lack of anonymity, etc almost literally justified by "just think of the children".