This is cool because it avoids emulation. However I think it has many shortcomings today which could all be solved by emulating a real CPU architecture (e.g memory protection support, ecosystem with tooling and Linux distributions).

By the way I have developed a similar project, WebCM, a RISC-V emulator capable of running full Alpine Linux that can be embedded in the Web browser and can reach up to 500 MIPS for some users, which I think is pretty fast despite the emulation, you can try at https://edubart.github.io/webcm/. Booting is also fast, it always boots from scratch when you open the page, so you can boot fast even with emulation.

That indeed feel fast, awesome stuff!

That is excellent!