Author here! :) This article is me sharing something that made me really happy, wanting to show others how they can do the same.
I see some comments pointing out that the clock wouldn't need to run in the browser. I picked this option to make it simple for folks around me to quickly prototype their own clock faces. This isn't supposed to be the cheapest or most efficient implementation, either; feel free to build your own LCD clock and then blog about how you did it!
Its a genuinely nice idea, I do love the second clock face you've done, the sort of "fuel gauge" one. I think a great next step would be some sort of gallery of clock faces that people can use and contribute to, based on whatever code you've used to create them
Indeed. Don't be dissuaded by Hacker News commenters. All the naysayers here doesn't seem to have published their own blog posts about how they built circular LCD clocks with Arduino ESP32 and low level programming or whatever they fancy as "good enough".
Browser based rendering that allows people to easily make new watch faces with JS and SVG is a perfectly reasonable platform for a nifty project like this. I think your watch faces look neat.