What an inane simplification.
At this point organizations like Hamas get MORE support, as they are fighting against Israel. When people are disposed and have family members killed, they don't throw all emotion out the window and think "maybe if I grovel and become a murderer, things will be better".
It's not a realistic solution, and it wouldn't work anywhere. How do the Palestinians even know WHO is a part of Hamas? How do they, in this chaos, organize anything like that? How do they prevent more people, people who've just lost their children, fill the holes in Hamas that we're made? And most importantly, how do they know that doing any of these things will give them a better life?
It's all bullshit roundabout justification and victim blaming, throwing all this on Hamas, what Israel is doing is wrong and they are the ones with both the power, organization and moral/legal obligation to stop this.