There are plenty of Jewish people who consider "Jewish" as being both a religious and ethnic identifier. I used to think of Jewishness as purely a religious description until I actually met some Jews (I moved from a tiny village to a larger town that had a decently sized Jewish community, and one of my close friends was Jewish), who disagreed with my impression. For additional context, I live in the UK, so your blanket statement about Europe does not apply to the level that you state it.

"the last people that tried to make it an ethnic description were literal Nazis."

Given that there are many Jews who recognise "Jewishness" as pertaining to both religion and to ethnicity, in the present day, it seems quite inappropriate to make this comparison. I realise that you're seeking to denounce Israel's ethnonationalism, but it's possible to criticise Zionism without having to deny the existence of Jewish ethnic groups. Hell, one of the things I found especially powerful about my local pro-Palestine demonstrations was seeing how much I learned about Judaism by working alongside secular Jews and religious Jews brought together by anti-Zionism.