“As Jews, throughout biblical and rabbinic literature, we claim superiority.”
We claim that Hashem chose us, and if we are “better”, it is only because we were chosen by Hashem.
This is something that the Torah clearly says and not something that we “claim”. To my knowledge, the Torah does not say that about any other group. There may be characteristics that are more likely to be found in certain groups, but I don’t think it ever says that each person in a particular group has to have that characteristic (although maybe I’m wrong).
The only possible exception I can think of is Amalek, but even with Amalek, I don’t think it’s so clear-cut. For one thing, b’nei Haman are learning Torah in B’nei Brak, so there clearly are exceptions. Also, I think there is an opinion that Amalek is not genetic but rather, a certain type of person.