This is correct and indeed unfortunate. Another thing I didn't mention in the post is that the driver for the XDR's USB bus is the same as the one for the Studi

This is correct and indeed unfortunate. Another thing I didn't mention in the post is that the driver for the XDR's USB bus is the same as the one for the Studio Display's ports+camera+audio. I imagine the only way they'd have support "spatial audio" is over USB so they just went that route from day one