"My main issue with it is this: that it aligns the Xbox One with the past right at the time when the console should most be focussed on the future."
This is inane. BC was the most requested feature by a mile. It was one of the reasons I considered not buying one initially. People have dozens, sometimes hundreds of older games and would like their new, powerful system to be able to play them as well. And now they can - and it's going to drive even more sales.