I’m assuming for the sake of this exercise, Wii’s final year was 2012 and Switch’s final year is 2022.
Wii sold under 5 million units in 2012 and didn’t have a single major release, outside of a Kirby collection, a Mario sports compilation, and Xenoblade (in the US).
Switch is projected to sell 25 million this FY, so I’ll be conservative and say it will sell 18 million in 2022 (it’ll probably sell more) and has Pokemon Legends, Splatoon 3, 3D Kirby, Bayonetta 3, BotW 2, and probably another half dozen unannounced first party titles.
I think Switch will survive until 2023.