Why can't minors under the age of 12 play mobile phones?

Under the age of twelve is a good time to study, because playing mobile phone delays learning, which is not worth the loss.

/kloc-The eyeballs of minors under 0/2 years old are not fully developed, and playing mobile phones will directly damage their eyesight.

/kloc-Minors under 0/2 years old have poor self-control, are easy to fall into it, have poor ability to distinguish right from wrong, and are easily influenced by bad things on the Internet.