Imagine that every day at midnight, every person in the world randomly switched bodies.
What would happen? Everyone would eat their favorite foods with no regard for the health consequences. No one would ever do any exercise, except for kinds of exercise which are inherently enjoyable. There’d be a lot of smoking, drinking, and doing drugs, etc., because we’d face no long-term health consequences of such. Obviously the health of the human race would deteriorate horribly. We might even die off.
This is what happens when there is no property, when people have no stake in the long-term management of a resource or asset.