You are right, reading books becomes less and less frequent in digital world.
But, you know, i noticed several years ago (when i started spending more and more time with the laptop and wifi) - when you read an actual book before going to sleep - your dreams are more vivid and you fall asleep faster.
But when you have a computer or phone or tablet in front of you before you pass out - you fall asleep longer and hardly remember anything from your dreams in the morning.