It feels like a bit of both. The phone is probably a focal point for other issues. But, I don't think we should downplay the fact that the finely tuned, variable reward scheduled, Skinner boxs that are many modern apps are anywhere near comic books, rock'n'roll, or videogames of old. I'm pretty conscious of intrusive notifications and apps that aggressively vie for my attention. Even with those limits in place, I'm acutely aware of the effect of having reddit available from my pocket in < 2 seconds. Maybe I'm weak, but I feel that it affects most of us in a fundamental way to some degree.

I'm not saying that you said anything counter to this. I just think that apps which are hyper-tuned to captivate our every moment are a different beast.