SteamOS would be a particular poor choice as a desktop operating system compared to basically any other Linux distribution. It uses an immutable file system and reverts all system changes upon every update. That's nice if you don't want to fuck up your handeheld gaming device with some dumb changes, but it's generally not what you will want on a device you use for all kinds of things. Of course, with some effort you can work around this, but then, why don't use a system that doesn't just use such a paradigm in the first place and won't roll back your workaround to make it usable with the next update?