At one point, it looked like Xbox had cracked the code. It was 2007-2008: They had Crackdown, Halo 3, Forza Motorsport 2 from their studios. They got BioShock as a third-party exclusive (like Sony does regularly today with Final Fantasy). They also were able to publish a bunch of good smaller games like Alien Hominid HD and Aegis Wing, and were on the front foot when it came to getting and promoting quality indies.
I don't know what happened, but it's like as soon as 2009 hit, Xbox division fell off completely. Part of the problem is Bungie moving on and 343i being a garbage developer. They basically have taken Halo, a premiere IP in the '00s, and made it a mediocre IP with minimal hype. But the other part of the problem is that they can't get anything published in-house except for Forza and the occasional mid Halo game that falls off the radar almost immediately.
This is a dev that was consistently publishing games of all types in the OG Xbox era, many of which were great (Halo: CE and Halo 2, Top Spin Tennis, Forza, PGR, OutRun 2, Mech Assault, Jade Empire, etc.). There is no reason for this sort of fall off.