Something I've come to realize in the discussions of this thread is that even though the Wii was initially crazy successful and had a shorter replacement cycle than its competitors (while still taking 6 years to be replaced), the problem lies in the Wii's specs and approach. The Wii had pretty garbage specs (even for 2006 standards) and that hurts the longevity of the console in terms of first and third party support. The Switch is a different case because it's a hybrid. Yes, its specs as a home console can be pretty garbage. But it is a clear generational leap over the 3DS and Vita in terms of the handheld market. Plus, the motion controls on Switch are more tastefully integrated.
So even though I do believe the Wii was killed off too early, they really would've had to shift the focus to justify waiting until 2013 for a successor. We would've needed more first-party support like Star Fox, another Mario spin-off, and maybe some remakes. We also might have needed a Wii Pro or something in 2010 or 2011 with at least 128 MB of RAM, a slightly faster CPU and GPU, and HDMI support.
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
