So things TC has gotten wrong Assuming the Steam system is called the Steam Box Assuming Steam Machine is limited to Steam OS Assuming Steam OS is limited any more than other Linux versions. Grammar Punctuation
So basically his entire post is him being uninformed or screwing up.
First thing I think of when I hear "Steam Machine" is... http://i.imgur.com/p17DLA4.jpg
BUT: Right now the worst thing about the steam OS is that not all games are going to work with it... Eventually they'll make Linux more popular for gaming (hopefully) and then it'll be a great alternative OS for people who use their PC to play games rather than do spreadsheets and/or file taxes (though I see no reason why SteamOS wouldn't do those things as well).
TC seems to think that the "steambox" is a console with an OS devoted to nothing but steam... That actually seems to be a pretty common misconception...