Keeping in mind that the term "genocide" as a bona fide war crime was first used in reference to the holocaust, and given the fact that attempts to normalize holocaust denial have become subject to universal scorn and ridicule all over the world in the face of overwhelming indisputable evidence that confirmed the systematic eradication of 6 million Jews, the next best thing Jew haters could come up with was to propagate the mythology of "genocide" committed by the "Zionists".
This propaganda began way before the Gaza war. It can easily be traced to the post-1967 antisemitic propaganda in the official press of the Soviet Union, the inheritor of the centuries-old traditional pan-European antisemitism, and later to the post-1980s Iran, the propaganda powerhouse of the pan-Islamic antisemitism.
Of course, neither "genocide" nor "Zionist", as the terms have been used in this more contemporary incarnation of antisemitic activism and are still used with the same purpose and effect today, have anything to do with the laws, ideologies or even semantics that define these terms, but this doesn't matter when propaganda controls the narrative. Enormous resources have been spent on making this propaganda effective. Thus, "Zionist" has become a derogatory term being applied to all Jews while retaining the facade of plausible deniability by not referring to Jews directly, and "genocide" is likewise being used now as a pejorative, free of the obligation of having to preserve the appearance of legality and credibility associated with the term, being applied to the Jews in general, not just Israel or Israelis, or Israeli government.
"Genocide, like "Zionism" is now commonly used in certain circles as a derogatory reference to the Jews in general and as an excuse for antisemitic rhetoric, intimidation and violence (remember the incident in the NYC subway in which pro Hamas "freedom fighters" demanded to know if any passengers were Zionist, and if they were, gave them the "last chance" to leave the train?).