Trump lives among the 1% where they don't have to interact with computers to get around in society. He has aides and servants to conduct much of the routine paperwork and other things that ordinary people need to do to function with government and business. That includes email for communications. It doesn't surprise me that in his world, he uses phone calls and personal meetings to conduct most of his face to face business. It is definitely isolating and he lives very differently than most other people. Interestingly, I see the same situation with homeless or poor people who aren't as plugged in with everyone else.