Zionists are ethno-Fascists - Fascism linked to ethnicity rather than the nationalism of traditional Fascism - complete with things like ethnic superiority beliefs (and a general belief in some ethnicities being ubermensch and others untermensch), accusing critics of that Fascism of being against the ethnicity and surrounding themselves with the symbology related to the ethnicity.

It's the same kind of Fascism as the NAZIS - who claimed to represent the Arian Race - had, complete with rabid racism and inhuman levels of murderous behavior against members of ethnicities deemed untermensch (who Zionists literally call "human animals") and not at all the same kind of Fascism as, say, Mussolini (in Italy) or Franco (in Spain).

Zionism is far closer to NAZIsm than any other ideology, including all other Fascist ideologies, and their words and actions reflect that, so calling them NAZIs as a shortcut makes sense because that's pretty much what they are, with the main difference being the ethnicity they claim to represent.

Sure, you can say they haven't committed a Holocaust and the NAZIs did, but then again the NAZIs too didn't start by committing a Holocaust - that only came later because nobody stood up against them until it was too late, exactly the same as being done with regards to the Zionists.

The Nazis weren't just anti-Jewish, they were anti-anyone who isn't Aryan. While the people here are basically only showing anti-Arab sentiments, if they held the same view to all other races then they would be analogous to Nazis.