I personally think that responsible smartphone use should be learned and practiced, rather than outright banning them.
I think this shows that adults are terribly addicted to their devices and think if they can’t stop using them, children won’t either. They certainly can’t teach how to use phones responsibly if they can’t do it themselves. Unfortunately for children the result is an outright ban.
Smartphone use is certainly something that should be decided on local level. Global bans only make sense for universal human rights, or things like climate change that have global effects.