ChromeOS is pretty far from normal Linux. It’s closer to something like Android. Uses the Linux kernel, but doesn’t bring the freedom, flexibility, or even GUI tool that come with a Linux desktop. SteamOS does come with all of those.
And, importantly, improvements and software for SteamOS is, generally, improvements and software for most Linux distros.






Apple always refers to iPad’s OS as “iPad OS”, not iOS. I wonder if the browsers make the same differentiation in their user agent strings.