In order to make such a law enforceable you will need age verification and identity checks on all social media, device level controls, expanded data access and collection. Put simply it's a privacy nightmare and it's not unlike the government to trojan horse privacy infringement by using the time tested "think of the children" mantra.
Parents need to enforce this.
I love how everytime something like this happens you see the utter contempt for the working class your average leftist has. Lenin and Trotsky essentially thought the "masses" had to be pulled kicking and screaming into class consciousness because they are too dumb to know what's good for them after all.