The underlying issue is obviously that children have nothing better to do than to be on a smartphone and that school is an oppressive, boring, hostile, unnatural environment.
The answer isn't to take away their coping mechanism, it's to treat a human child like it should be treated. A young boy should be offered opportunities to partake in martial arts clubs, hunting clubs, robotics and programming competitions, fitness training, house building projects, general machinery and electronics projects and on and on the list goes. My honest opinion why society absolutely refuses to help children is because it is full of adults who envy and fear the children. They know that a 12 year old could do 80% of their job within a year if given the smallest amount of encouragement and instruction. Real life isn't allowed to compete with the virtual world, that's why the virtual world is winning in the child's life.