Ontology talk:9k/RD/Q618-BuyResidentsForProsperity/SPS6-17
Geoism won't die based on large groups of people all going to war with large groups of people. It will die based on individual White people handing a plot of land to their children as fast as possible before a Black person can get it, and when the Black person claims the system is unfair the White people accusing him of harrassment and stalking for getting too close to their plots while putting White individuals on as many plots as possible to the point they recreate homeless people and then they can shoot or imprison the Black man. Swap out "Black" for almost any ethnic group or political faction that has sufficient animosity toward another one; Russians and Ukrainians, pro-transgender atheists and anti-transgender Christians (the United States is a mess), Sunni and Shia inside an unstable country, etc.
It isn't scarcity or competition that actually turns tensions into wars; a better way to characterize it is that wars happen when two groups of people have incompatible conceptions of what should be legal or illegal for everybody on earth and both try to exclusively push those laws onto each other. That problem exists the moment socially-linked groups of people have a form of morality. Even if you divided two groups of arguing people into separate countries you're not safe from that, because entire countries can just claim that other countries are "violating international law" and then try to take away their sovereignty (especially with the help of multiple other countries that agree with them) and conquer them to force them to have a particular set of laws.
A geoist system would have to start from a particular countable group of people, and the current amount of land, money, and political power they all have right now is going to determine how successful they are at actually getting that system established over any larger area and protected by law as opposed to getting conquered by some other countable group of people believing in a particular set of laws who believe their laws are universal and based on human nature and should apply to everybody.