The author uses a lot of the same reasoning I do for using a bullet journal. (Some people like making theirs more elaborate or add more complexity - I keep mine very simple.)

Though I do like the idea of keeping the text document synced everywhere.

The thing I like my bullet journal for over a living document and using sticky notes, is that I can see very easily what I have accomplished. I started getting frustrated at never having everything done that I wanted. After starting the bullet journal, I could actually see what took up my time, and I was able to cut myself a lot more slack.