As a parent of kids that I don't want using smartphones just yet (oldest is 10), screw those reps. If my kids save up and buy a smartphone behind my back, that's on me for not earning their trust. If I'm such a bad parent that they feel the need to do that, they should have that right.
So screw these lawmakers. If they want to protect kids, they should teach parents how to be good parents, and teach the necessary stuff in schools.