I think GP is thinking of fiber optic Thunderbolt cables probably.

https://www.amazon.com/FIBBR-Female-Active-Extension-Optical... provides USB-to-fibre-to-USB in a single cable, and a copper pair in parallel for power.

Some USB4 / Thunderbolt cables are like that, but with copper in the middle. The drivers on the device end wouldn't be able to maintain signal integrity over that size of cable, so there's a pair of transceivers in each end of the cable to convert the signal into a format that'll survive transmission.

Seems like you can get 3m optical usb-c cables. Oculus sells an official "Full featured USB active optical cable. USB 3.2 Gen 1 Type-C" for tethered play.

That's what the cheatsheet says so maybe that's part of the spec.

What's the difference between talking USB and being USB?