I don't think that comment was an indictment of anything. As someone also in the space, it reads to me as a thoughtful explanation of why catching up to the CUDA ecosystem is so hard, even when the goal is "just" matrix multiplication (it's actually not, but for the sake of a cleaner argument that's ok). It's entirely possible AMD or Intel or someone else has some super secret CUDA killer hidden away somewhere, but nobody has seen any evidence of it. It's a bit of an extraordinary claim, and the community would love to see some extraordinary evidence.