This is api-level backwards compatibility for a library that is bundled with the games. Microsoft is fanatical about BC when the alternative is to break a piece

This is api-level backwards compatibility for a library that is bundled with the games. Microsoft is fanatical about BC when the alternative is to break a piece of software. When the only people they're inconveniencing are developers, the philosophy changes. And rightly so, otherwise it's just that much harder to build new features.