I've swapped Windows for the latest SteamOS build on my Legion Go S and I'm not going back
The latest stable SteamOS update, version 3.7.8, has finally brought in official Legion Go S support, making the handheld the first certified non-Steam Deck SteamOS device. There's a SteamOS version of the Legion Go S launching in a couple of days, but this also means the Windows version that's already in the wild should now officially work with SteamOS, too.
This latest version of the OS also packages "improved support for other AMD powered handhelds (like the ROG Ally and original Legion Go)"...