The idea that another huge failure like the Wii U would make Nintendo into a better company is dumb.
You know what would ACTUALLY happen if the Switch 2 failed? Nintendo would start putting more resources into their crappy gacha-filled mobile games and put less effort into their console games. Genshin Impact has made $15 billion in microtransactions; the mobile market can be extremely lucrative and has much lower development costs. The failure of the Wii U is the main reason why Nintendo started making mobile games in the first place.
Also, a failing Nintendo would focus even more on their biggest franchises like Mario/Zelda/Pokemon/Animal Crossing. You won’t get any more Metroid, Star Fox, F-Zero, Kid Icarus, Golden Sun, etc. if they are failing.