I think Trump is accustomed to thinking his spouses are lesser beings that exist only to bolster his image and serve at his pleasure, and he probably harbors deep feelings of disdain for all of them that he can't express publicly.
So for him it totally tracks to be married to a type of person that you hate.
This isn't a bad thought but it implies that he remembers she is married to a Jewish person. He definitely doesn't. He can't even pronounce her name or pick a wrong pronunciation to go with.
And Trump's wife, mother, and grandfather are and were immigrants, but it doesn't stop him from hating immigrants. That type of inconsistency isn't an issue for him, so I imagine calling Harris an antisemite is perfectly reasonable to him.