Without the facial hair, he just looks so much younger. The notebook makes sense if he was writing a lot, think about how much of a nuisance it would be to not only keep a digital note-taking device charged, but also keep it from breaking/getting damaged in a hike. He mentioned to other hikers that he deleted all social media — so he did have a digital presence at one point. I wonder why he took so much effort to hide his identity and where his wallet went. I hope the DNA testing is helpful.