I’d argue that most anti-Semites are probably fine with a Jewish ethnostate if it means no Jews in whatever country they’re from.

The inconsistency lies with their application of who is “ethnic” and needs to “go back where they came from.” They ignore the fact that white people are not indigenous to North America.

Obligatory Sartre quote regarding anti-Semites:

Never believe that anti-Semites are completely unaware of the absurdity of their replies. They know that their remarks are frivolous, open to challenge. But they are amusing themselves, for it is their adversary who is obliged to use words responsibly, since he believes in words. The anti-Semites have the right to play. They even like to play with discourse for, by giving ridiculous reasons, they discredit the seriousness of their interlocutors. They delight in acting in bad faith, since they seek not to persuade by sound argument but to intimidate and disconcert. If you press them too closely, they will abruptly fall silent, loftily indicating by some phrase that the time for argument is past.

Not really. Anti semites want Jews to go away. Israel is away. There is no inherent contradiction in them supporting Israel. In fact, there is significant ideological alignment between anti-Semitism and Zionism, as both tend towards ethnononationalism.