I think the parent poster is referring to the technological explosion that preceded WWI, where social conventions about how war ought to be waged had yet to take into account the ruthless efficiency of modern warfare (tanks, cars, radio, telephone, submachine guns, planes, chemical weapons, flamethrowers, indirect-fire artillery). It was a 19th-century war fought with 20th-century technology; similarly, current generations are trying to reconcile 20th-century methods of social organization with 21st-century tech. I don't get the impression that they were literally trying to compare the experience of fighting in WWI to being on Reddit.