Everyone that feels like it is outrageous to believe this is evil and there is likely a super reasonable explanation for this should consider that this is not a novel thing. At Netflix and Amazon Prime limit the resolution on Linux to 1080p and 720 respectively. Of course the reason is a different one, but Xbox Cloud would simply get in line with other major video streaming providers. It's natural to assume that it might be true and the reasons are silly, just like they are for every other platform.