You cannot regulate peer pressure, even with the complete ban you would still have kids using other platforms for social interaction and have peer pressure, like on roblox or whatever
This has never stopped anyone. For example, Climate change legislation makes little sense unless implemented worldwide. War crime or anti-terror legislation doesn't really make sense unless it's implemented across borders (and pretending doesn't count. Nobody's even talking about arresting Putin, or anyone else for that matter). Taxation ...