Sure, that's true. Now the bigger question: who'd bother writing those games primarily-for-Ouya in the first place? You've got Windows PCs right over there, Macs and Linux PCs accessible without
too much more work, and if you play your cards right, you can even deploy to the 360 (yeah, XNA's EOL'd, but it's still viable for XBLIG, and that's a lot better of a controller-based platform than Ouya is).
In the rare, doubt-it'll-happen case of a hit game coming out first on Ouya, I would bet we'd see it on Steam, for cheaper, within six months--because porting will, by necessity, be That Easy.
Ouya could, depending on tech stack get a port in that situation (and I've considered it for my own project because I'll already have a gamepad API for the Windows/Mac release), but it will never be a leading platform that people actively target because the market share is infinitesmal. There are too many better options in front of it.
EDIT: Also, bear in mind that Ouya isn't doing anything groundbreaking with their gamepad stuff - the gamepad APIs already exist in Android 4.x. The only Ouya-specific stuff I have seen is in their purchasing layer.