Books force you to actively chew on the information you're consuming; digital content is generally pre-processed to make consumption effortless but often lacking in nutrition. A truly well-written book can not convey its message in less words than it uses; if someone cannot process 30 pages worth of content then their comprehension has an upper bound. I've had to fight for my attention span and would encourage anyone else who struggles with reading to start practicing with YA novels to build up the mental muscles required to get through the tough stuff.