Well yes, actually they probably should be. More people require more land. What entitles any group to land if not necessity? Why should a minority be allowed to claim for itself a majority of the land and resources? And more importantly, how? What is going to prevent the larger population from just taking what they perceive as their "fair share" (regardless whether this perception is true) of the land by force? Indigenous people were defeated before and their numbers were much greater and the material, organizational and technological advantages of the settler state was not as great back then as it is now.

The scales are even more tilted today, there is no reason to expect anything but a repeat of the previous result unless a different strategy is adopted, namely of appealing to a significant enough portion of the settler proletariat to recognize that the settler colonial state model no longer serves their best interest. The decline of capitalism is too advanced and the free lunch they got through robbing the indigenous population and expanding into their land is no longer sufficient. You described the brutal and genocidal methods that the settlers have used to beat the indigenous population into submission in the past, what do you think they would do today and how do you plan to guard against being starved out, having your crops burned, your waters poisoned and your land made uninhabitable? Because there are enough of them who would rather make sure no one can use that land if they can't have it.

It is also a very unwise thing to do to keep insisting that the settler majority is still able to benefit the same as before from maintaining the settler-colonial relations. You are in effect making the argument that their interest is best served by holding on to all of the land since that enables their system to continue. I believe this is not the case, i believe the colonized peoples have a chance to succeed today where they did not succeed in the past precisely because the conditions are such that capitalism can no longer be sustained through the same methods as before. Because it is becoming the best interest of more and more of the settler proletariat to ally with the colonized nations and to overthrow the existing socio-economic and political order. If this was not the case as you seem to imply, i would struggle to see any hope of success. People will not go against their material interests for the sake of moral righteousness.