I'm not going to dig up a quote because it simply isn't worth my time to leaf through my books to satisfy your personal gripe. If you're a generativist, great, knock yourself out. I'm not going to argue the semantics of "dismissive" with you either.
Chomsky has been incredibly uncharitable to other theoretical paradigms. Rational people can accept (even celebrate!) his contributions and at the same time acknowledge that his lack of diplomacy has been deleterious for the field. Obsequiously leaping to his defense over stating something so uncontroversial is totally unreasonable. I like Givón but if he acted like a jerk I wouldn't have a problem saying so.
I'm not going to continue this (nor will I * gasp * "retract the claim"). Take care!