Remote play is already semi-broken on stable. In the sense that the video renders super dark unless you disable hardware decoding.
https://github.com/ValveSoftware/SteamOS/issues/1246
The beta and preview channels are even worse. The remote play session will just never load at all.
https://steamcommunity.com/app/1675200/discussions/1/3757725080156008363/?l=czech
https://github.com/ValveSoftware/steam-for-linux/issues/10461
It seems like this is slipping through the cracks. I’m making this post to raise some awareness on the issue. Not sure what we can really do though.
Edit: God damn it valve.
Annoying thing about moonlight and sunshine is that you can’t use your existing controller configs easily.
If you set up the moondeck decky plugin you can use your configurations without any hassle.