Microsoft was in prime position this gen to cause another major split coming off the back of the Xbox 360, they fumbled very hard.
If Xbox One came out of the gate swinging and was a value proposition as compelling as the PlayStation 4 without all that policy nonsense the PS4 wouldn't be where it is now. Would it be successful? Absolutely, but the reality is the split would probably be in 70/80 million neighborhood instead of a 100/50 million split.
The Xbox One did fumble hard with its original message, but that's hardly the only issue.
Look at the discrepancy in games for the entire generation. They've been dropping the ball the entire generation.