Here is some peer-reviewed research on how little an affect parent control of phone usage has on phone addiction: https://journals.lww.com/jan/fulltext/2018/04000/does_parent...

There is a multi-billion dollar concerted effort by the largest companies in the world to get an iron grip on the attention of children at a level of granularity never before seen - don't pretend like that isn't a novel cultural force that should be reckoned with.