You're right. No claim was made that he was correct on all matters. However, that comment provided no substance beyond a list of credentials. The claim is that

You're right. No claim was made that he was correct on all matters. However, that comment provided no substance beyond a list of credentials. The claim is that he is an expert on all matters related to programming; none of those credentials have anything to do with OS, ISA, or hardware development. Certainly a claim that he is more of an expert than anyone here, which is absurd because HN does not consist of a uniform sample of human beings. Much less uniform in the comments section. People who care to comment on posts like this are passionate about what they do; meaning that they are most-likely very good at it. He might be able to design the best computer system for a narrow scope - which has already happened in some respects: we have Vulkan, which he very curiously avoids, instead opting for the heavily abstracted OpenGL. His opinions are valuable and worth listening to. Others' opinions are not worthless merely because of his CV and social network status.