I understand the logic that UNESCO is trying to make. However instead of a global ban on the device itself, ban the addictive parts of it. TikTok and most other corporate social media are designed to keep everyone, kids and adults alike as addicted to the platform as possible. Phones are still a valuable resource for a student, including being able to call in the event of an emergency or having access to maps or other things.
Ban the actual evil on the phones, not the phones themselves