Calling a Linux distro Gnu/Linux today is wrong because the actual Gnu code running is such a small part of everything.
SteamOS uses Linux as much as Linux distros like Fedora and Arch and other Linux based systems like Android.
A lot of gamers are also FOSS folks although not as hardcore as RMS.
Not at all, it makes a point, ChromeOS, WebOS, Android, are also based on the Linux kernel and hardly considered Linux distributions for everyday use, in a way similar to GNU/Linux expectations.
How little do game studios care to port their titles from Android/NDK into SteamOS, even though both are "Linux".
You have a misunderstanding. SteamOS is essentially Arch Linux.
Edit: Misunderstanding is mine. I think you guys are discussing something else. I was trying to assert that SteamOS is GNU/Linux, unlike the others.
Android and iOS games are usually not interesting for SteamOS gamers.
What really makes ChromeOS different from Ubuntu except it is not developed in the open?
Userspace is a browser.