>
Before cellphones you would just stare off into space (you're not getting any deep thinking or deep work done waiting in line) or would just browse the gum or trash magazines.The key is that the "before cellphones" behavior often involved a greater connection to one's immediate surroundings, or being "present". The risk/concern with browsing a phone in these moments is that it promotes disconnection and feeds our brain's need for that next dopamine hit. Some hypothesize that this constant disconnection from "here/now" is part of society's broader problems and people increasingly look at the real world through the lens of social media, which we know to be a major distortion of reality.
Disclaimer: anecdote, sample size of one, etc...for me personally, I've been working hard not to fill those idle moments and instead focus on being present and stay in the moment. This could literally be as simple as noticing the variety of gum options in the checkout line. I already have dissociative tendencies due to PTSD, and one of the most effective ways for me to dissociate is to lose myself in the endless scroll. Conversely, staying present/connected to my surroundings helps my mental state immensely.