It is worth setting the expectation in the CheatSheet that WebMCP is in early preview, under active development and the API surface is changing frequently as a result of that, otherwise users of the cheatsheet might be surprised when some of the APIs documented there don't work.
Btw, Web Bluetooth is not only supported by Chrome, but also by Edge, Samsung Internet and others. More on supported browsers on https://caniuse.com/?search=web%20bluetooth