I wouldn’t me one to make rumors, but when I think NX, I think FX (as in chip, or expansion). Now my idea on how it could go, which may ruin this plan, if it was their plan, well I thought a thing up, since it would be “unsolicited idea,” I won’t tell them.
I had the idea of a drive, even with expanded process and graphic side lined and running a dedicated Hard Drive (for the game) cart loading like system. The same possibility, can exist with an optical. Imagine, an optical disk, working through a current system, running it’s own graphic and processor with a loader, small enough to fit mobility and as strong as the game needs to be. Really the rest is just monitor and controls. Even as a HD type or Game Card style.
Devs would be running the required processor control, you could even put OS on such a card bay. Find a way to update removable media, you also have an ability to change things enough to shut out the hackers, and have on-disk/card/cart save states too.
They can always solicit my mind’s eye, but I wouldn’t hold my breath.