I think it’s more pointing out how many politicians (and people in general), especially Republicans, who won’t criticize them, and even say criticizing them is anti-semitic. Him being Jewish means he has more cultural connection to them than they do, yet he still points it out. He also can’t reliably be called anti-semitic because he is a semite (at least the modern meaning of the word. I’m not sure if he speaks Hebrew or other Semitic languages).