Your argument boils down to "it's not genocide if they aren't really human ;)" rationalizing. It's quite easy to "other" any group, or be convinced to do so by years of media propaganda. See how some people here do it to the Jews.

That said, applying morality to group conflicts is silly and is what social justice warriors do. Nobody deserves to exist. It doesn't matter if they are a positive influence or not. Ultimately the only thing that matters is force. If Palestinians don't have the ability to defend their territory, they don't have territory, or a right to exist. Simple law of nature. Whether they should be allowed to live in their old homelands in Israel or not is a different question.

I can probably synthesize our positions together by restating your demand for proof as "does it benefit Israeli to stop killing the palestinians?" or "does it benefit the United States to help the palestinians?" Then I can agree with you that the answer is no. I don't know see how it benefits us to help Israel either. Military and economic reasons exist, but we can always swap one ally for another. Syria, Lebanon, or Jordan could all be excellent partners in the region.