This is statement so ridiculous it verges on not even being worthy of being called unfalsifiable. It's plain old personal incredulity that because Chomsky cannot comprehend there are limits to human thought, human thought must be infinitely various, and because he uses language to describe thought, language must also be infinitely various. Thought is not infinitely various and language is even less so. This is blatantly obvious from even every day experience. How could language express an unlimited array of thoughts when language cannot even fully express the experience of eating a chicken nugget? Can language express all your thoughts when looking at a sunrise? When embracing your lover after a hard day? Language is the best tool we have but that doesn't stop it from being an extremely limited form of communication.