I tried gamescope before (trying to get HDR working) and it seemed to work ok (though I couldn’t get HDR working), I just tried it with tenfoot and while it launches, the controller doesn’t work for me (with cyberpunk) so not sure if that helps your or not

https://i.imgur.com/MOWYgpZ.png

For me, I get stuff in the steam logs like this:

wlserver: Running compositor on wayland display 'gamescope-0'
wlserver: [backend/headless/backend.c:16] Starting headless backend
wlserver: [xwayland/server.c:108] Starting Xwayland on :1
wlserver: [types/wlr_compositor.c:681] New wlr_surface 0x55945e26c8d0 (res 0x55945e13cd60)
wlserver: [xwayland/server.c:273] Xserver is ready

Command I ran was this

gamescope -W 2560 -H 1440 --steam -- steam -tenfoot

https://i.imgur.com/ZfuzgfA.png

Used gamescope from their github site.

I just tried it and it seems to work for me also:

https://i.imgur.com/WXF1CPp.png

https://i.imgur.com/awdLFPi.png