This is a maddeningly cynical and ironic argument, and seems to be a corollary to two of the standard Zionist tropes: (1) Everyone is anti-Semitic and (2) Israel is always the victim.
The fact is that Israel is a signatory to the Genocide Convention, and the convention was written and implemented at the behest of the Israeli State and its allies in the wake of Israel's founding.
Such an argument goes to the base nature of the peculiarly Zionist interpretation of the motto, "NEVER AGAIN" - a motto that Zionists developed but one which they only apply to themselves (i.e., ":never again to us").
It is a particularly vexing argument because Zionists have steadfastly refused to recognise other genocides, such as the Armenian genocide, because they fear it will lessen their "unique" place in history as the people who have suffered more than any others.
I would argue that they should hold to their signature on the Convention and that they, above all others, should steer well away from anything even hinting at genocide because of their "unique" place in history.
