I disagree. I have an 11" Air for portability but I still use my iPad to read my books and magazines. Nothing beats a tablet to read books, magazines, brochures and surf the web, watch the stuff on You Tube, especially when you are traveling or consuming these materials in bed. Also, for short travels, my iPad is sufficient to keep me in touch with the rest of the world and small enough to leave the Air at home, yet large enough to view everything comfortably as opposed to doing it all on an iPhone 6+.
If that makes it a luxury item, so be it.