> On the flipside, there is the theory (I think even Copetti brings it up in their XBox 360 Architecture breakdown [0]) that IBM using the Cell PPE for the 360's tri-cores left a sour taste in Toshiba, but more-so Sony's mouths.

It's more than a theory. It's pretty much spelled out explicitly in The Race For A New Game Machine how salty not just Sony and Toshiba were in the broad sense, but also the Sony and Toshiba engineers that the IBM team worked with felt pretty betrayed.

Intel did release a few generations of their Xeons with an Arria built in but it's been a couple years since the last release. It's a cool idea but I think all the money dried up quick once the AI boom started. Plus they spun off Altera so I doubt they'll be doing it again.

I think Nintendo used Tegra because it was super cheap. AMD has access to the same ARM cores as everyone else (see Seattle and Sound Waves) but a semi-custom chip would have been more expensive than an overstocked Tegra.