The Xbox brand is worthless in Japan. It's pretty much a done thing and I don't think it would be worth anyone's effort to do anything more for it. There simply isn't a market for it. It's been 13 years since the Xbox first launched in Japan, and there hasn't been a single piece of software which could sell more than ~200k. At the same time, the brand is successful enough worldwide that Japan literally no longer matters. Even if they sell 0 hardware and 0 software total moving forward in Japan, the system will still have no trouble at all securing big Japanese titles like FF, KH, RE, MGS, etc as long as publishers have any interest at all in the international market. And if publishers don't have international plans for a title, then it would be pointless to MS anyway.
some UK retailers are ridicuously fast to put nintendo products on clearance and give nintendo the middle finger thereafter.
I wonder if that will ever happen in Japan with microsoft.