Thanks for pointing that out, I didn't realise how few games work on SteamOS.
The other point would be is it worth Sega's time? They would probably make so much more money just leaving it dedicated to Windows rather than trying to make a Steambox work.
Maybe if Steamboxes become a hit when some dedicated hardware guys try them out, then Sega might decide to play in that space, but I don't see it happening any time soon.
That is the thing as I mentioned, Feral handles the OSX TW ports.
The only Linux port to my knowledge(excluding potential 3rd parties) Sega has themselves funded is FM14, and the initiative was apparently at least somewhat successful because FM15 is also getting a linux port.
With regard to OS ports, Sega doesn't actually publish the porting of TW to OSX. Feral interactive port it themselves and they are the publishers for Total war on OSX. So I assume either Sega funds *some* of the porting or none of it. So as of now, Sega is currently funding FM15, Rome 2, and COH2 I assume due to the fact that it has linux code in the SteamDB entry all internally.
Empire looks like it is being ported by feral again, similar to how Aspyr ported and published the Mac and Linux version of Civilization 5. So Sega doesn't have to port all the games internally, they can contract companies or even individuals like Ryan Gordon to do their ports.
Again, my main concern is that even in the even that sega pursues a steambox, games will not be ready to launch with it for some time, and that is a problem.