I think the post needlessly interprets EY as bounding the complexity of the brain to at most that of the genome. Of course the brain's complexity reflects the learning environment - but, important as that is, in this context it doesn't seem very relevant. It's not that hard to "raise" an AI in an environment much like those humans are raised in. (Maybe that's not a good way to create Friendly AI - or maybe it is - but I take it EY's argument was about AI in general.)