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The PS2 dominated its three home console competitors in a way that is rarely seen, even knocking one of them out of the game in 2001 as the other two were arriving.
Switch may be in a blue ocean, but it doesn't have that dominance. PS4 and Xbox One were about halfway done when Switch launched, and now we have their successors. It's kind of an apples to oranges situation, but there's still a slight effect.
I don't see Nintendo screwing up the launch and first year of the Switch's successor, which will also cut down on Switch sales.
My more generous estimates for the Switch are 140-145 million lifetime. I would say it's well over the halfway point by now.
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
