Dead people do not produce excess value, alive people do.
I hate to think that way but if you put yourself in the shoes of a capitalist exploiting Palestinians with the help of Israel I think would be much more profitable than killing them.
Just like in Germany during WW2 capitalist interests give way to fascism and hate.
I do agree that it is settler-colonial project.
I also do not think land is the main purpose of the genocide. I think the extermination of Palestinians(and other Arabs) is the main reason, taking the land is a very good additional incentive.
But neither I nor You can know what happens in the heads of genocidal maniacs so we can only guess.