I don't understand how this isn't an obvious problem with the argument that "they voted for Hamas." If you paint all Palestinians with this brush, the exact same logic can be used to paint all Israeli as warmongering genocidal psychopaths. Or perhaps that conclusion is tacitly accepted by the people making the argument and therefore using the reverse as justification for their actions is kosher.
Most people in Gaza were not born yet when the last election was held. The median age of Gazans in 2020 was 18. Also, 1. was it a free and fair election? 2. was there good alternatives? 3. Does that mean the children deserve to die? 4. What do you think happens to the children thay grow up in a genocide? Do you think they a) become upstanding, healthy citizens? or b) become radicalized? Violence leads to more violence. Noone is born a terrorist, but Israels far right government's genocide is creating them.