That said, I don't think it supports casting "back" to the laptop that you're using for Mac Virtual Display. That would be a big improvement I think.

Realistically, if it's something on my Virtual Display, I just take of the VP for a moment and my MBP screen comes back on.

ETA: I just tried to stream back to the MBP that I'm using with Mac Virtual Display. It "works", but not in the way I'd hoped. My view is streamed to the MBP, but the screen doesn't come back on - instead, the virtual display shows what I'm seeing in the headset. Not helpful, and more than a bit nausea-inducing :(.

"Universal Desktop" is the best IMO at the moment, as it supports streaming individual windows in addition to the entire desktop. It's far from perfect, unfortunately, but it's a step in the right direction, and shows what will be possible soon.

I originally thought I wanted multiple virtual displays in visionOS. After using a couple of tools that support that... I've realized that's not a good use of the technology. I think per-window streaming is the right way forward at this point.