Nintendo Switch 2 Dock USB-C Compatibility

"Test 5: DR_SWAP always rejected"

That means the monitor tries to change its own role from USB host (which it defaulted to because it's the power source) to USB gadget. And the Switch rejects the request because it sees itself as the USB gadget (for example to exchange data when you connect it to a PC).

The article itself also says "Our monitoring of the interactions with the USB-C monitor shows that the negotiation does not even get to the point of the Vendor Defined Messages(VDM)" so I see no hint of foul play by Nintendo. (And why would they? They are not in the business of selling USB monitors.)

My guess would be that the connection failure is due to a firmware bug in the monitor. But I am also heavily biased here because my last Asus screen had A LOT of firmware issues.

> And why would they? They are not in the business of selling USB monitors

Not true, they block nreal to make them pay the store fee for an enabling app to make their usbc mini monitors work with the switch.

Assuming that you are referring to the Nreal Air VR goggles, those cannot accept a regular video signal over USB-C. They are NOT monitors. For making them work, they need to do pre-processing of the video stream on the host device, thereby degrading gaming performance. That's why they need an app, because they lack an integrated CPU/GPU and that makes them not compliant with the USB-C monitor spec.

And I believe that's also the real reason why Nintendo would block them: They make otherwise fluent games stutter, which will reflect badly on Nintendo and the game developers. Because people in general won't know that their Nreal Air is stealing some of the Switch's GPU performance and that they are creating performance issues themselves.