"Antisemitic" to refer to people who follow Jewish traditions is an appropriation. Arabs are also a Semitic people, for example. See Semitic language family.

Aryan or European or whatever you want to tall them non-Semitic peoples are uncomfortable with Semitic peoples living among them too much or in too disruptive a way for the same legitimate reasons any group would feel uncomfortable with such an arrangement with outsiders. Same sorts of reasons some people in Israel would like for it to remain predominantly Jewish.

Please use appropriate terminology. I know a lot of people have been taught that "antisemitic" is the correct word, but it's not. The correct word is anti-Jewish, anti-Zionist, anti-Judeist, whatever, unless you're actually referring to a negative sentiment towards Semitic stuff and not just to Jewish stuff specifically.