do you know of any that actually exist? All I can find are active cables that go up to 15 feet which is a lot better than the 3ft of copper but still a far cry short of running to another room easily
I don't see why they shouldn't work; all the translation logic is in the active circuitry at each end, and the low-level protocol and USB-C spec was designed with this use case in mind, so nothing expects a continuous copper connection between both ends. Obviously power delivery doesn't work over that type of cable.