The majority of the complaints I hear about notebooks I think come from a misunderstanding of what they're supposed to be. It's a mashup between a scientific paper and a repl. So it's useful for a bit of both: a) Just like with a paper, you can present scientific or mathematical ideas with accompanying visualizations or simulations. From the REPL side, as a bonus, you get interactivity, and the reader can pause and e…
If you ever have used an R Notebook written in R-Markdown, then its pretty easy to see why Jupyter Notebooks putting everything in JSON is just... infuriatingly wrong-headed. In an R Notebook, I can see my code, I can see my text, everything is exceedingly simple to understand, and I can edit it in any of the fantastic text editors out there (Jupyter's editor is not among them)
It's also trivial to export notebooks to .py files.
That said, my goodness do notebooks wreak havoc on git. I hope this in particular gets fixed as popularity grows.