Israel has nuclear weapons and f16s. If they tried to commit genocide they would succeed. If Palestinians had those weapons, they would literally commit genocide immediately as it is stated in Hamas’ founding charter.
Israel is dependent on foreign aid, do you think their allies wouldn't notice if they bombed and killed millions of people at once? There would be a response from other countries in the area as well. Even the Nazis took a lot of effort to hide the holocaust during the execution of it. Where in Hamas' founding charter does it state "we will commit genocide if we have the power."? And even if it did, Hamas is not the Palestinian people, they haven't had an election since 2006 and there are several other militant groups within Palestine.
“After some general explanatory language about Hamas’s religious foundation and noble intentions, the covenant comes to the Islamic Resistance Movement’s raison d’être: the slaughter of Jews. “The Day of Judgement will not come about,” it proclaims, “until Moslems fight the Jews (killing the Jews), when the Jew will hide behind stones and trees. The stones and trees will say O Moslems, O Abdulla, there is a Jew behind me, come and kill him.””