Earlier quoted context omitted.
E-Mail and Python notebooks? I don't think they these are the primary use cases for a "digital paper" device. What you consider an "overengineered piece" of paper might be intentional. Maybe you don't need paper - some people do.
I think that as e-ink gets better and better refresh rates, that having it as a grayscale monitor for things like textbooks/markup and browsing the web will make sense. Having an e-ink tablet to browse HN, check email and read the morning paper sounds pretty nice. I used to get the NYTimes delivered to my Kindle each morning.
Could you clarify your meaning? Because as far as I know, there hasn't been any improvement in "refresh rates". Typical update times are still around 600ms. Unless you mean tricks like A2 as used by vendors like Dasung which aren't real completed updates.