I swapped over to a Sunshine host (non-NVidia version of Moonlight) + Moonlight client combo for game streaming and it absolutely blew Steamlink out of the water for me. Went from lag, resolution switching and disconnects to buttery smooth on my Pi400 at 1080p.
Host PC is AMD graphics which the host end of Moonlight (the game streaming tool) doesn't support, but there is an open source fork called Sunshine that you can use instead. It's a Windows 10 machine, so no need for Linux and is wired to my LAN with a powerline adaptor.
Client is my Raspberry Pi 400, running Moonlight, on the latest version of PiOS with my controllers bluetoothed. It's wired to my LAN with a network switch and connected to my TV.
huh I was using the nvidia shield and switched to sunshine when they shut it down. had heaps of issues then went to steamlink which seemed better. last game I tried was slow as though, maybe I should give sunshine another run