I think that is a bad example. I haven't heard of Jewish people being offended by Ferengi, but anti-Semitic depictions are very often exactly "ugly, greedy people" (just look at any Nazi propaganda). Once it becomes a common thread it works less as a defense.

I imagine "small hands" would similarly work poorly as a defense against a defamation suit from Trump: he doesn't have to claim he has small hands, only that he is often depicted as having them.

In the case of the Ferengi, "ugly greedy people with big noses," specifically greedy for an in-universe gold analogue, short, always cheating people; the analogues with common anti-semitic stereotypes are certainly there.

Then again Armin Shimmerman, who played Quark and is Jewish himself, has said that people in different countries see different stereotypes in the Ferengi - such as the Chinese or the Irish - so it probably depends on one's own own cultural indoctrination.

I think a better case could be made for the Klingons being racist caricatures, since in TOS their look was intentionally based on Asiatic and Mongol people in order to make them seem more frightening and villainous.