The 4G/5G Public Warning System is fundamentally designed for instantaneous earthquake and tsunami response.
It's a bit like modern day equivalent of air raid sirens, or incoming nuke alerts, even. And as such, it's just unfit for things that don't require immediate and full alert. AMBER alerts are just not good use of it.
It's another instance of: give a politician a fish and watch him smear it on the walls to stink up the place, throw it in the garbage and then complain he's still hungry.
What happens when you teach him to fish :-(
You can't, they're incapable of learning.
Hey, that's what the people want