You could say this about absolutely anybody.

You could say this about the Nazis, you could say this about a random murderer on the street, you could say this about Israel. You haven't lived any of their lives, you don't know how they're feeling, so is it "arrogant" to say that what they're doing is wrong?

If you're unable to say, clearly and unequivocally, that killing and raping innocent people is wrong, nothing else you have to say is worth anything. You can try to empathise with why they do things that are wrong, I try to do that too, but that's different to just shrugging your shoulders and saying, "Morality doesn't exist when the group I've decided are the victims do commit atrocities."

Again, that is exactly what the people defending the current genocide are doing. They've decided that Israel are perfect victims who can do no wrong, or at least whose wrongs are always justified by the circumstances they're in, and they shrug their shoulders while people die.