It's not much, but at least Biden is malleable on this. He can be persuaded to make the attempt to try to slow the Israelis down, maybe even stop arms shipments to Israel altogether (or at least add conditions). If Trump comes in, he'd probably go in the complete opposite direction out of spite for liberals and would try to help the Israeli genocide even harder. It's not a great choice, but the choice of least harm in this case is still Biden.
Israel is not the only problem in that area, mind you. Just wanting them to stop what they're currently doing fixes nothing in the large picture.
Hamas deciding to surrender and Palestine somehow waking up seems like the best option, but I don't see how that could happen. And Israel's actions are not helping that of course.