Sony and Microsoft cannot keep up with AMD and Nvidia's arm race. RX 470 is faster than ps4 pro (ipc jump is huge from a cross fire 2011 gpu to rx 470) Scorpio is already slower than the rumored vega 11 (being slightly downclocked version but a Navi equivalent would destroy it ) that is on par with gtx 1070. And by the time Volta and Navi came around the thing is all over again. Microsoft have win 10 to retreat to (and Microsoft was smart enough to move their content to help their operating system than anything else), Nintendo was out of the arm race and PS4 is practically Sony's last leg. And sony's exclusive right now was not nearly as attractive.