finally somebody dares to say it: Chomsky's wrong.
(It's also quite obvious that a linguist would say that "language" is of the utmost importance).
QUESTION: It might help if you could define how you use the term “cognition” as opposed to the term “language.”
CHOMSKY: Well, I wouldn’t use the term “cognition” as opposed to the term “language.” Rather, cognition is an overall term that includes every system of belief, knowledge, understanding, interpretation, perception, and so on. Language is just one of many systems that interact to form our whole complex of cognitive structures.
It's the Weak Sapir-Whorf hypothesis that is much more interesting and still at debate. Certainly things that are easier to describe in a language would seem easier to reason with. Our brains leverage language as a tool to map concepts and the concepts we can name are easier to grasp and utilize than the ones we cannot.
The Weak hypothesis does seem like it would be affected by brain elasticity. Keeping concepts close to hand in your language would presumably keep them easier to conceptualize as your brain plasticizes.
I will agree with the author that, despite being not possessing language, animals are more intelligent and sensitive than frequently given credit.
Have you ever had the experience of having to stop in mid-sentence, stuck, because a word was "on the tip of your tongue"?