I'm pretty sure Xbox One and PS4 to Xbox Series X/S and PS5 have to be the most similar platform totals YTD of any generation to the next in history.
PS4 is barely above the PS5 YTD right now, and it's similar with Xbox One compared to the Series.
What could shake things up is the replacement year. 2013-2020 was the launch to replacement cycle of both the Xbox One and PS4. The strong rumors right now are that the Fifth Xbox will launch in 2026 and PS6 will launch in 2028 (maybe 2027 at the earliest).
So realistically, a 2026-2027 launch for the Fifth Xbox and a 2027-2028 launch for PS6.
With the current YTD figures in mind, a PS6 launch in 2028 would likely mean PS5 would outsell PS4. And even if the Xbox Series X/S isn't discontinued right away when replaced (like the Xbox One was), a 2026 launch for the Fifth Xbox would likely mean the Xbox Series X/S falls short of Xbox One lifetime totals.
Lifetime Sales Predictions
Switch: 156 million (was 73, then 96, then 113 million, then 125 million, then 144 million, then 151 million)
PS5: 115 million (was 105 million) Xbox Series S/X: 48 million (was 60 million, then 67 million, then 57 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
