Might makes right bullshit. I'm not even going to address your comparison to indigenous tribes in America (who also experienced a genocide), but in any case there are still people alive who remember having their lands dispossessed. And keep in mind that the majority of people in Gaza are essentially refugees from this exact dispossession, and the dispossession continues in the West Bank right now with illegal settlements. Modern Israel refuses to respect the internationally-recognized borders established by the victors of WWII, and Netanyahu himself has signaled many times that all Palestinian land is Israel, even though there are currently Palestinian majorities in many parts of those areas.

Also, they are not refusing to leave buildings, what in the absolute fuck are you talking about? Over 100,000 people have left their homes to shelter. They are often given less than a minutes warning, if they are even given a warning. I saved this quote from a couple of days ago:

Another resident, Abu Mohammad Hassounah, said his brother lost two of his children in the attacks.

“The Israeli army… told one of our neighbours that the building has to be evacuated. Where should they go? They should go to the sea. People started running and suddenly we heard an explosion,” he said. “My brother’s two children were standing in the doorway. They were killed.”

They do not take pride in dying, Hamas does. The conflation between the two is frankly disgusting and appalling, especially when there haven't been elections since 2006 (and before you say that they won a majority, they didn't, they won a plurality with 44.45% of the vote and Fatah getting 41.45%). 70% of Gazans support a return to Palestinian Authority rule, even if a majority express some support for Hamas (https://www.washingtoninstitute.org/policy-analysis/polls-show-majority-gazans-were-against-breaking-ceasefire-hamas-and-hezbollah). This isn't even mentioning that the reason that someone would support Hamas is directly linked to the conditions of dispossession and the present conditions which amount to an open-air prison.

And the fact that, as you say, "They cry about it occasionally but no one takes them seriously," is the problem.