https://www.gamespot.com/articles/its-a-myth-that-xbox-one-backwards-compatibility-i/1100-6453995/

One of the Xbox One's standout features is backwards compatibility support for Xbox 360 games. There are more than 400 titles in the catalog right now, and the library is seemingly always growing. Microsoft is committed to backwards compatibility now and in the long run, Xbox boss Phil Spencer told GameSpot at the Brazil Game Show today.

In June, there was a report that said Xbox One owners "largely ignore" the backwards compatibility feature. Microsoft responded by pointing out that around half of all Xbox One owners have used the feature, tallying some 508 million hours using the service. Spencer doubled down on this, saying it's categorically untrue that it's an ignored feature.