Maybe the new models aren't equipped with AMD chips ? Also AMD had to cut profits on the previous console CPUs IIRC. So that's not a "value" for the stock market.
Both are powered by AMD, and it has been confirmed for almost a year.
It's still semi-custom AMD silicon (but new and improved!). I don't think they could actually switch GPU architecture within the console lifecycle without breaking things, and there's also nobody to go to anyway (who else makes semi-custom high-performance x64 SoCs, let alone with decent graphics?).
Yeah I was overly cautious, it would be high risk to pull the rug at that time.