It's "Minecraft" in the sense that there's blocks. He had to heavily gut most of the features to get it to work.
Cool project though, kinda has micro python vibes of "oh wow, this is almost the real thing but it runs on a disposable vape"
Edit: I guess this does work as a proper server for the older versions. You just have to use the simplified world gen and chunking setup since that's how it's able to be memory efficient.