I guess I just don't share the sentiment that giving every child in a classroom unfettered access to content designed to distract them while a teacher is trying to teach the class is a good thing. I'm having difficulty understanding why you'd need to be convinced that it isn't.
I have two teenagers and it doesn't sound like it's a huge problem. And attempts to stifle phone usage (yondr pouches) are just creating friction. Maybe having a phone out is very obvious but kids have been doodling, daydreaming, talking and passing paper notes forever. If the downside of phones was so overwhelmingly obvious we wouldn't have such a dearth of measurable evidence.