90% of what 90% of people say just doesn't matter. So it doesn't matter if they're staring at their phones instead of talking about their weekend plans or their cousin's weddings, or any other tidbit of nothing that occupies their public vocalizations.
The problem is the companies that shape their services provided through the phone to be optimized towards abusing well-documented behavioral characteristics of 'average people'.
But then, when I was in college, I'd read paperbacks while riding a bike to class.
Twitter sound bites have slowly weakened my attention span for more long form articles. You can easily see this by looking at what sites are popular (Buzzfeed) and which are struggling to stay alive (rip Grantland)