Those agreements would be >15 years old at this point, I doubt AMD would agree to sandbag their entire APU lineup going forward just to make the base model PS4 and Xbone look good, and I especially doubt that they would do that again with the PS5 and Xbox Series when they actually had money and room to negotiate. Likewise, it doesn't make sense as a restriction Microsoft or Sony would impose: the console business is one of convenience, not power. They aren't trying to beat PCs and they don't care if PCs are a better deal. They care if they can get you to buy a box that locks you into their DRM scheme.
Furthermore, during the chip shortages of the last few years, AMD was actually selling broken PS5 silicon for use as a normal Windows PC[0]. If there were restrictions on selling APUs above a certain performance level, then this PC wouldn't exist.
Historically PC OEMs cared about price more than graphics performance so that's what they got. If you look at mobile SoCs or the eDRAM-equipped SKUs Intel made for Apple you see more emphasis on memory & graphics performance similar to consoles.
