I think the problem is that most students, (as this study shows) are not figuring it out on their own, at least not in high school. It feels like you're one of the outliers, not the common case.

Having rules about what you can and can't bring into school is nothing new. I went to high school in the 90s, and there were plenty of things we weren't allowed to bring with us into class; back then, the closest analogue to smartphones would have been pagers, probably.

It seems entirely reasonable to ban smartphones (and dumb phones, even) from schools. Frankly, I think it's absolutely insane that they were ever allowed.

And sure, maybe these students who go to high schools where smartphones are banned will get to university and go nuts, sitting in lecture halls with their phones out all the time. They'll learn very quickly that their grades will suffer, and will clean up their acts or fail out of school. But this is like everything else: the first year of university is the big year of independence, of being away from parents for the first time, and college students do plenty of dumb things in the name of that independence. That's always been the case; I'm no stranger to that phenomenon myself. They either work it out on their own, or they fail out.