The irony of all this is all the people who were so worried that some future version of Windows might become a closed system with all purchases going through the Windows Store are now excited about Valve taking an open-source OS and making it a closed system where they are the only source to buy your software.
Your premise is flawed, and you're just trying to take cheap shots at the OP rather than addressing this actual topic.
1) To use all aspects of Windows 8, you need to sell through the platform holders store. That's not 'crazy tinfoil hats 20 years time' thinking, that's the reality of now.
2) Valve have explicitly said that they would make a steambox open. Even if they didn't, Valve aren't the platform owners of Linux in a way that MS are with Windows.
Even if Valve become the shittiest, most anti-consumer company that has ever existed, any work done in making Linux gamer friendly benefits everybody forever.
The system comprising off-the-shelf parts, of course. That one costs $4 billion in 2000 dollars at 20 million units and is still losing when you put a bullet in its head, while even the most miserable heavily-customized failure peaked at $4 billion lost in 2006 dollars around a year after launch, and has been slowly recouping since.
1) If your business model is so retarded that you spend $4 billion day one and never sell a single unit, sure.
2) The Xbox 1 to this day has never recouped the losses it made. It never will recoup those losses. It's dead, and every unit it ever sold cost MS money. Pretty much any other company that didn't have a massive ulterior motive for price dumping the thing would have killed it off year 2 or 3. As it was they couldn't wait to get the 360 out there so that they could kill it off, because every unit sold cost them money.