Ars Technica - Analysis: Why SteamOS probably won’t cause a PC gaming
Anyone looking to buy a SteamOS box this year is going to find it nearly
impossible to avoid one major downside when compared to a Windows machine:
the library of games that are playable natively on SteamOS is much smaller
than that for Windows and will likely remain so for the forseeable future.
It's not a small difference, either—Steam's online store currently lists 486
games that run on Linux compared to 2,483 that work on Windows. The 75
percent of the Steam library that doesn't run on Linux includes an
overwhelming majority of the titles on Steam's top sellers list as well as a
number of big name titles that most any potential SteamOS customer is going
to want to play.