1. His project does allow rendering any HTML: https://www.invisible-computers.com/programmable-e-paper-scr...
2. It is in stock. :) Raspberry Pi Zero 2 and the waveshare displays are in a bit of a stock crunch, and the frame I ended up mounting this in, along with the special flat USB cable, pushed the project cost to the same price. It's my own aEsTheTic tho.