In theory, it is done to protect children from potential abusers, but humanity's greatest atrocities were carried out in pursuit of supposedly noble causes, so nothing new here.
Well, that's a good theory to totally make privacy of the citizens non-existent but I believe it wasn't done for that noble cause, but to attack privacy of the citizens. I know it's valid point that children should be protected from the abusers but those abusers can be anywhere not only on internet. Looks like privacy is become a big burden for the centralized system and in future people might just remember privacy as a term but it may not exist in next 2 - 3 decades.