You have good points, but I still see it as a worldwide 2018 release. New Leaf came out in Japan way back in November 2012 and Summer 2013 in the other major regions. Nintendo waiting 6 years to release a main series Animal Crossing title would be nuts and unprecedented (though the Switch has already done plenty of unprecedented things).
Nintendo skipped a main series Animal Crossing game on the Wii U, and the spin-off on the Wii U was poorly received. I think 2018 is still the best bet since I see Metroid and Pokemon as 2019 releases.
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)
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