Get that plate of crow ready.
There is a chance both the PS5 DE and Xbox Lockhart come in less than $400 with the latter looking to be a $300 machine. Sony is cultivating markets in emerging countries that will grow in the PS5's lifecycle. MS is in overall better position with their studios and vision which should lead to higher lifetime sales.
In terms of high end sales, I can see the Xbox Series X reach anywhere from 60 to 70 Million, while the PS5 reaches 130 - 140 Million. Low end sales will easily be above the 120 Million combined. There is still a chance for the PS4/Xbox One to outsell the PS360 lifetime units combined.