The last time AMD got into a fight with Intel, Intel pulled out all the stops. The only relief AMD got--quite a ways down the road--was in the form of damages. https://en.wikipedia.org/wiki/Advanced_Micro_Devices,_Inc._v....
Something tells me AMD decided to make strange bedfellows this time around against a common growing threat in multiple spaces, to include graphics as well as machine learning (nVidia). It's one agreement, but for AMD, it's both a revenue source as well as a foot in the door for potential collaborative efforts which could give it some stability as it broadens its offerings and looks at new avenues for value creation in the face of headwinds such as resistance in further transistor shrinkage.