100 years ago, many people saw no need to pay for this new-fangled thing called a motorcar when a horse-and-carriage seemed fine, nor a reason why they should buy a new car every N years because of the need to upgrade. Yet somehow, people decided they wanted to go through the hassle of learning to drive and paying significant amounts of money to buy a car as well as fuel, insurance, MOT, etc...because it made life easier.
Nobody is forced to have a smartphone... but when travelling, and particularly when flying, it makes life easier.