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Hmmm. Well the Switch would still be available, and getting some games.. They manufactured the Wii U for over 4 years despite the fact that it tanked. They would've rode out the 3DS even longer than they did, likely releasing non-remake/port 1st-party games well into 2019 or 2020. A dedicated handheld successor more powerful than PlayStation Vita but weaker than the Switch would launch in 2019.
I have no idea what they would do in the home console space. For them to make a home console at with at least Xbox One X specs (let alone Xbox Series X and PS5) would take so much time and investment. I'd say they would try a beefy home console like this, but I don't think they could even get it out by 2021 or 2022.
Basically Nintendo's hardware division would be pretty screwed for a while if the Switch failed, considering they've been behind on specs in the home console market since the Wii.
Lifetime Sales Predictions
Switch: 161 million (was 73 million, then 96 million, then 113 million, then 125 million, then 144 million, then 151 million, then 156 million)
PS5: 122 million (was 105 million, then 115 million) Xbox Series X/S: 38 million (was 60 million, then 67 million, then 57 million. then 48 million. then 40 million)
Switch 2: 120 million (was 116 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
