I fly a lot and most people are using their phones now without issue. But when someone does have an issue I remind myself that many people rarely fly, and haven

I fly a lot and most people are using their phones now without issue. But when someone does have an issue I remind myself that many people rarely fly, and haven't been through the process hundreds of times. Phone, paper, whatever - people screw it up if they haven't done it before. Boarding first, pre-check/global entry are all beneficial in part because you're dealing with other frequent flyers.