The USB-C port on some of Nvidia's RTX cards is actually primarily meant as a "VirtualLink" port, designed for running a VR headset over a single USB-C cable, rather than requiring multiple separate connections for video, data and power.
However, as of now, 18 months after the GeForce 20 series came out, there are still no VR headsets that support VirtualLink that I know of. Valve originally intended to have an optional $40 VirtualLink dongle for their Index headset, but it would have not been particularly useful for desktop computers as it still required multiple connections to the dongle, and few laptops supported the feature, where it could have served more of a purpose. Valve also claimed to encounter "technical issues" with it...