artbrooks - Give credit where credit is due. In addition to being a professor of linguistics, he:

...is a member of the American Academy of Arts and Sciences, the National Academy of Sciences, and the American Philosophical Society. In addition, he is a member of other professional and learned societies in the United States and abroad, and is a recipient of the Distinguished Scientific Contribution Award of the American Psychological Association, the Kyoto Prize in Basic Sciences, the Helmholtz Medal, the Dorothy Eldridge Peacemaker Award, the Ben Franklin Medal in Computer and Cognitive Science, and others. He is twice winner of The Orwell Award, granted by The National Council of Teachers of English for "Distinguished Contributions to Honesty and Clarity in Public Language" [6]. Early in his career Chomsky was granted the prestigious MacArthur Award.

Chomsky was voted the leading living public intellectual in The 2005 Global Intellectuals Poll conducted by the British magazine Prospect. He reacted, saying "I don't pay a lot of attention to polls" [7]. In a list compiled by the magazine New Statesman in 2006, he was voted seventh in the list of "Heroes of our time".[22]

- from Wiki

It is his mastery of linguistics that has brought clarity to many subjects and has made political ideas accessible to many people. You may not agree with him but to describe him as an opinionated professor is to deny him the respect he deserves. He is not as one-dimensional as you seem to think he is.