Bazzite provides a Steam-OS gaming-centric interface out of the box. How are you going to upstream that? You think Debian stable is going to agree all of a sudden provide it's users a gaming console UI?
You can look up gamescope-session for more info.
Its something that I generally wouldn't expect on traditional mainstream distros.
Which as an aside, I think distros should advertise better. It must be awful to be sold on a distro only to find that it doesn’t support your newish hardware. A simple list of supported hardware linked on the features and download pages would suffice but a little executable tool that will tell you if your box’s hardware is supported would be even better.