It seems that most in Germany do not understand they’ll give even more of their online freedom away for no net gain.
Let’s mandate state-sanctioned age verification. Some service may accept this, other won’t. First loss. Then, some kids will get around that with complacent parents. Other will be pressured into it. In the end, it won’t work as a full ban. So, either turn a blind eye to the whole situation (then why bother in the first place), or make it worse: only one account per ID maybe. Big second loss there. And even if it works, it’s ignoring that some sites that would qualify as “social media” are the only communication outlet some people have. Third huge loss.
This will only be a terrible annoyance to everyone, prevent some services from growing or even exist, to the benefit of kids using their parents accounts anyway or VPNing around it. They learned how to do that very quickly for other online content.
Laws and rules that are unenforceable at scale are only useful to pin more faults on people when needed, not to help them.
Some vulnerable people (yes, that include kids) are manipulated and cut from external contacts, and sometimes online services are their only way to communicate. A lot of such services could fall under the “social media” category indiscriminately, making it harder to use, and cutting their only source of communications.
Think like countries banning TOR and the like to root out journalist, but on a smaller scale.