I agree that the price and lack of markets probably played the primary role, in addition to the popular conception that the PS4 was the more powerful machine (random UPS guy told me for sure Madden looks better on PS4). I also think when PlayStation and Xbox are on equal footing, Sony will always win because they just have a larger segment of the population that grew up on Crash, Cloud, and Spyro, solely by virtue of having been around longer.
That said, I think there has to be some incalculable variable, through which the DRM fiasco indeed had an impact. It drove the enthusiasts in the know insane and they must have had some impact on their immediate networks of friends looking to get into the next console generation.
Similar to random UPS guy above, I had some random guy walk up to me at Wal Mart, while I was looking at an Xbox One, and tell me not to get it because of all the online restrictions that it has. This was months after launch and well after Microsoft had already course-corrected. The damage was done and it was real.
As far as whether Microsoft is really back on track, I'm not so sure. People seem happier with the brand but from a sales perspective, there must always be some floor above which a console marketed by Microsoft will always sell in the modern day with the biggest multiplatform games on everything. Is the Xbox really selling well enough above that floor to consider it a success? With Red Dead taking a lot of the sunlight away from other titles, I think we're about to enter a late-generation slump like we did last gen, where big titles with great reviews might not sell as well as analysts would expect, and there will be talk again about the viability of dedicated consoles. The manufacturers need to be careful about how they manage this time, as well as what they deliver on the other side of it to shake off the malaise and jumpstart the next generation.