This.

The world is becoming increasingly more uncertain geopolitically. We have incipient (and actual) wars coming, and near term potential for societal disruption from technological unemployment. Meanwhile social media has all but completely undermined broadcast media as a means of social control.

This isn't about protecting children. It's about preventing a repeated of the Arab Spring in western countries later this decade.

"Think of the children" is the oldest trick in the book, and should always be met with skepticism.

The Arab Spring was caused by a tripling of food prices. I somehow doubt something similar will happen in the west. As for the rest, ignoring the population's concerns (by suppressing social media) is the best way to cause political violence. So I see blocking the governments desires to shape political discourse as saving the politicians from themselves.