just bc someone shares conclusions with fascists/nazis/etc., doesn't mean that the conclusions are wrong. trotsky (who is a bad guy himself) was denounced by stalin for criticizing the soviet system as "totalitarian." stalin would say "look, trotsky is saying the same thing as the US and ex-nazis and fascists in germany are saying." the implication being that if what he was saying was also said by the evil US and germany, then it must not be true. trotsky replied, rightly, "just bc facists are saying what i'm saying, doesn't mean its true, and it's not going to stop me from saying it."
noam chomsky has never denied the holocaust (read his writings on the holocaust) and the closest he came was to defend the right of a holocaust denier to speak (the Faurisson affair). chomsky, you see, accepts american values and thus assumes rightly that defending the right of a holocaust denier to speak his mind (if we can call it that in the case of a holocaust denier) is not the same as defending the holocaust denier's beliefs.
also, chomsky's conclusions on the state of affairs in the middle east and israel-palestine may be in the minority here in the US, but everywhere else in the world (asia, europe, south america, africa), it's taken as a given that the US is torturing the middle east for its oil and that israel is imposing apartheid-like conditions on the palestinians. now, do we then conclude that all of the world is anti-semitic and holocaust deniers? or is it that maybe perhaps noam chomsky's conclusions (shared by the rest of the world) on the middle east and israel-palestine have some truth to them?
every year, the UN votes on a resolution titled something like "peaceful resolution to israel-palestine problem" and every year the vote is something like 166-2, with the 2 negative votes being the US and israel. are all of those 166 countries full of raving anti-semites and holocaust deniers? or perhaps there's some truth to this alternate (according to US mainstream ideas) interpretation?
if you want to get a sense of what the rest of the world thinks, try looking up bbc or some other foreign source (the bbc is british, so it's the closest to the US in terms of opinions and so on, but it's still very different - the rest of the world makes the US look off the spectrum).
i also suggest that you read some more chomsky and look up his sources.