Last year, I read Paul Johnson's History of the Jews. He usually called such people "non-Jew Jews". They were self-hating Jews who eschewed everything that made the Jews unique. He included Jews like Marx and Trotsky when he used that description, so I guess an old Bolshevik like Bernie belongs on the list, too.
“Non-Jew Jews” is less accurate, because it could be taken that they were non-religious Jews or just rejected their ethnic or cultural heritage. It also doesn’t imply that they hate Jews or Israel.
This is why I selected “antijews”. Antijews can either be Jewish or not. But they reject everything Jewish and Israel. They do not despise part of the nebula of Jews and Israel, but all of it, in its entirety.
The antijews who still call themselves “Jewish” are oxymoronic.