@bold. That can all be done on the same console. It's purely about marketing if technical upgrades are totally out of the picture.
If a competitor offers the updates on the same console, doesn't that invalidate the need for a brand new console, unless there's some other considerable upgrade that requires a new machine (such as a performance upgrade due to better computer components)? So a console in your perspective is purely artificial and has no reason of being, since a competitor in that case could easy cut over your offering by making it an add-on and saving people the need to buy a whole new console.
This basically puts the nail in the coffin.
People already paid for the old-gen-console and don't buy another one (except the first breaks). So no, I can't follow your argumentation.
But anyways, fine, we have different definitions of gen. I accept that. Your definition says the XBOX won gen 6. Fine, keep your opinion. I don't see any reason to fight it, but for me PS2 won gen 6 not gen 5.