Observable uses JavaScript to render the page, I presume that's why it's broken for you (I use uMatrix myself as well).
It's supposed to show an interactive notebook with canvas-based images, describing how ordered dithering can be composed with error diffusion dithering to create a form of hybrid dithering that is somewhere in-between.
Really? Is half of the feedback I'm going to get here complaints that the webpage isn't static enough?
Look, it's a simple page with text and images describing what happens. There is a description of the algorithm.
But one of the neat things of this method is that you can combine any error diffusion method with any threshold map, so to illustrate the point I implemented the idea in an interactive page where you can combine 14 different error diffusion methods with 12 threshold maps and 3 input images, for a total of 504 possible combinations. My apologies for giving you easy tools to experiment.
If I go to a web site, and it's a blank page, that gives me zero information. It's quite trivial to have a fallback, even if it just says "Really sorry, I see you have Javascript off, but this web page does cool things that need Javascript, so you won't see much here unless you switch it on. I promise not to do evil things."
Well, I suggest you either tweet at Observable, or open a feedback topic on their forums. Either way, I'm not in charge of their website (and would not have been able to implement this stuff in a day on any other platform, so no, building a static site from scratch is not a realistic option for me).
It's supposed to show an interactive notebook with canvas-based images, describing how ordered dithering can be composed with error diffusion dithering to create a form of hybrid dithering that is somewhere in-between.