The law necessarily exists for parents that aren't tech literate, since we already have the ability to monitor and lock kids out from adult content.

Do we really think parents will notice that a kid has installed a specific executable? The purpose of this law is to allow parents to outsource caring out which executables are safe, so there is no reason they would check.

Plus a kid can just live boot from a USB if the parent doesn't lock the bios, which would give them an ephemeral session to do whatever they want without the parent knowing unless caught-in-the-act.