> But this addiction is much easier to break for most people than an addiction to something like say cigarettes (or even sugar).

Physically? I presume you're right. But here's the problem; you don't need cigarettes to accomplish any other expected, daily task in your life. You need your phone for a whole bunch of useful tasks that aren't health-depleting. I once read someone explain eating disorders in a similar way. You still need to eat, so you can't simply kick the root of your problem out of your life forever.