I'm curious about this bullet point. I would consider the effort of creating more content (articles, low-content books, etc) to be effort required to scale, which would eliminate any writing-based passive income. Is there another way of looking at this?

Edit: I hadn't gotten to the low-content books section and was thinking of a different kind of e-book -- nevermind on that one! Obviously you won't have to do any writing to fill a blank notebook!