Considering there are only about 10-15 gaming distro's, *most of those games can be installed manually.
You also have steam and wine
For your quake sourceport(s), there are many, just take your
pickI do build custom iso's with nvidia, wine, and steam installed, but not available to the public.
Most games/packages are just an apt away and are at a users disposal so really no need to include in a distro unless you are a gaming distro.