You could do that. With that image everything is vompletely equal on the user device which means that debugging is much easier. Ublue makes distributing custom fedoras increadibly easy.

installs all those things and sets things up properly on a standard fedora install?

That’s exactly what all universal blue images do. It’s just that setup is done every single day in github from scratch and stamped out as an image so that the end result gets to your computer as a finished deployment artifact. Leads to better update reliability, built in rollback.

The biggest benefit is that it’s easier for a community to fix the fast moving gamer stuff as a config layer on top of a distro that’s delivered this way than me having to manually figure out what component of my gaming setup changed that week.

How does it have a large attack surface? I thought being immutable reduced the surface.

That would be very very hard and unreliable.

Bazzite is more than just “preinstalled Steam”, it has a list of tweaks, optimizations and additions so long you can’t even finish reading it all! 😅
This includes a different kernel, pre-configured containers, and much more.
If you do that on a regular system, configuration drift would quickly destroy any good experience in no time and result in a huge mess.

This seems something with too big of an attack surface.

Not really.

• Most stuff is installed in containers
• The pros of image based distros still apply here in terms of reliability, security, etc.
• Its no more than a few hours away from upstream
• Most apps (Lutris, OBS, etc.) are optional and opt-in, if you just click “next, next, next” in the installer you’ll get a relatively vanilla experience compared to stock Fedora