* Paper does not run out of battery. On a ship where you need to be able to navigate whether or not the computer fails, this is a feature. My brother-in-law tells a story of when he was an air traffic controller in the military. Every so often they told them they had to turn off their computers and navigate the pilots in the air using paper to make sure they knew how to do it in case the computers failed and the power turned off.
* Paper cannot be hacked. In the article, Russian intelligence and MI5 were mentioned, as well as paper prescriptions. Of all highly secure mediums, paper is the most convenient.
* Paper is just handy. I use it right now to print out knitting patterns and write notes on them. I don't have to find some app to annotate the pattern I can just write directly on the paper. For what it is, paper is the default because it is so fully featured.