I mean Phil said it in an interview recently, that they had to wait until late Summer (I assume that means August) for their AMD chipsets so that they could finish their Xbox Series units. Supposedly PS5 was in production by late June I think. So it does make sense why Sony was able to get so much more stock ready for launch than MS. MS clearly weren't able to manufacture enough stock to meet demand, in spite of the fact that they saw their day one preorders sell out minutes way back in September.
Phil also said he had a finished Series X in his house in early May. And they showed off the final unit in Dec of the previous year at the VGAs. So which is it? Were they ahead of Sony, like Xbox fans were saying late last year and early this year? Or are they behind them, which only started being the narrative when the 12 Tflops beast narrative didn't quite play out?