Yeah, AMD was a bad business partner for Nintendo, from my perspective, Nintendo doesn't build GPUs, AMD does, so when Nintendo went to AMD to buy a GPU for a low powered Wii U, AMD gave them a 2008 architecture, and a year later gave Sony a 2012 architecture for less simply because Sony asked for the best GPU available at that price?
Nvidia goes to Nintendo and shows off Tegra K1, Nintendo gets Tegra X1 for half the price of the Wii U's SoC. Nvidia also future proofs the Switch enough that it is able to see ports from modern games. Just a vastly different experience, before Wii U, Nintendo was using ArtX technology that was built for the Gamecube, and then modified for the Wii. I think a major reason the Switch is such a valuable platform, is because of the performance that it can meet, which would have been impossible with AMD at the time, and with DLSS and RT performance being better on Nvidia, as well as lower memory bandwidth and capacity required for Nvidia architecture over AMD, the huge down grade towards AMD would be a death sentence for Nintendo's dedicated gaming business.
I think in just another 10 years or so, graphics will not matter much anymore, it's also worth noting that more and more games are starting to go to mobile, and soon that billion+ user market, will be a big focus for most of the major publishers in the industry, so graphics are not going to win in the end.