These are things that Harris would know if he had any kind of genuine expertise in his professed specialist area, so his errors speak volumes. And he then goes on, later in the discussion, to retort in the manner shown in the tweet below. I'd regard those responses as lame even if they came from a child.
The whole dialogue between the two of them reads like exactly what it is: an exchange between, on the one hand, a serious professional person who's eminent in his field and knows what he's talking about (Stefan), and, on the other hand, a bad-faith fucking simpleton (Harris).
EDIT - To make crystal clear which is which, though I hope people realised anyway! ;)