Likely aimed at the Steam Frame in particular. Interestingly, the WiVRn project investigated pyrowave too and found it wasn't really worth it, but perhaps the benefit is greater with the Frame and with less downsides (due to the included dongle).

EDIT: And here's the original blog post from the pyrowave creator.

It's worth noting that this is a high bandwidth codec. The latency is great, but most people will need wired internet between both devices to have good results from it.

It’s about time they do something about Steam Play. It was kinda ‘okay but not the best’ a decade ago, and has only gotten worse as other streaming services got better

What do you mean “INTRODUCES”? I’m using it for in-home streaming over Punktfunk for weeks now?