Seeing as PS4 and Xbone games usually use the same settings albeit at different resoultions. Xbone games running at 4k isn't going to be ugly.
Yeah thats another thing as well, a lot of people question how perfect IQ can get with native 4k and HDR on the go but it's one of those see-it-to-believe-it things
But please MS, dont forget the games. Thats the stuff that sells first and foremost, i'm sure they'll deliver in the multiplat department but keep that first party variety coming.