Not everyone views their child as an enemy that just happens to be in close quarters with them. Most people trust their kids to generally not do bad things. People keep knives in their kitchen and kids, explain the danger, and kids are generally responsible enough to not play with them.

If this is a concept that you can't grasp, then words will never convey it. It's simply a detachment from reality to think people are viewing their phones as a loaded gun and their child as someone hellbent on betraying them and causing massive societal damage.

The phone is the YouTube device. If they get a notification that their kid ordered from Amazon, they'll cancel the order and tell their kid not to do it again. It's seriously that simple. Just go and talk to a parent. They'll think viewing their phones as a WMD is insane.