We have to be careful about accidentally defining racism out of existence. On a biological level race does not exist. There is no difference between a white person and a black person, beyond the very superficial.
But to me it stands to reason that if you believe you are racially superior and then discriminate on the basis of that, it’s racism. That’s really where it ends. A semantic argument about the nature of race isn’t going to help with anything.
It think it’s obvious that the discrimination and persecution the Jews have suffered through history has been the result of the belief that they are a separate race. Therefore it’s racism.
On a side note, isn’t it interesting that whenever anyone concludes there is a superior race, it’s always their race that happens to be the superior one 