They do, and an earlier version of my post mentioned that but I edited it down.
However, FIDO mode does not speak the keyboard sub-protocol. This means on the one hand it's not useable out of the box with some random device that allows USB keyboard input like the custom Yubico OTP mode is, but on the other hand it's able to deliver a good UX while having excellent security properties that would not be practical using keyboard emulation.
