This will be a tighter race than Generation 8. Microsoft seems to have learned from most of the stupidity of their Xbox One strategy (namely at the beginning).
PS5 will sell less than PS4. The PS4 is looking at 120-130 million lifetime hardware sales. PS5 might surpass the PS1, but I don't see it touching the PS4. The PS4 did so well largely because of Nintendo and Microsoft being stupid.
I can't say that Xbox Series X will sell more than the Xbox One, because I genuinely believe this will be the final generation of Xbox hardware. At the very least, I don't think it will do significantly better or worse than the Xbox One. The Xbox One will probably make it to 53-55 million lifetime hardware sales, and that's not too crazy for the Xbox Series X.
Lifetime Sales Predictions
Switch: 151 million (was 73, then 96, then 113 million, then 125 million, then 144 million)
PS5: 115 million (was 105 million) Xbox Series S/X: 57 million (was 60 million, then 67 million)
PS4: 120 mil (was 100 then 130 million, then 122 million) Xbox One: 51 mil (was 50 then 55 mil)
3DS: 75.5 mil (was 73, then 77 million)
"Let go your earthly tether, enter the void, empty and become wind." - Guru Laghima
