I have personally used the parental controls on Android, iOS and ChromeOS and to be honest they are terrible. Issues with syncing changes, the terrible UX for parental access control (iOS...), issues around audit/access logs, issues around prompting the parent for access.
I am honestly shocked that Apple known for its polished experience hasn't been forced by angry parents.
My daughter's school actually advised parents to not enable parental controls on her ChromeBook because it would interfere with the school's education websites but my daughter was caught playing web games in class so we decided to lock her down anyways.