So the current situation with out-of-control phone use in schools is interesting/puzzling to me, because clearly something's changed since then—but I don't think "better smartphones" are the differentiating factor here. Something's shifted with how schools enforce (or don't enforce) these policies, or with kids' relationship to their phones (and believe me, I was plenty hooked on mine back then too :P), or something else entirely.
It's also puzzling when people argue that smartphones have opened a Pandora's box that makes it impossible to control student behavior—because I know firsthand that that's not true!
[1] I think the threat of punishment also forced us to be relatively discreet about it. If you're texting in class, you have your phone on silent, brightness all the way down, barely sticking out of your bag...
[2] Some teachers admittedly gave more of a shit than others, but I rarely saw students taking advantage of that in a disruptive way—the most blatant thing you'd see is a kid listening to music on headphones during art class or something. I might've been the biggest offender in that regard, because I would occasionally bust out a Wiimote and N64 emulator to play Mario 64 on my phone, but I knew when I could get away with that and when I couldn't.