"All the land was claimed by others before we were born"

Not necessarily. All species need to scavenge for their own subsistence unless they want to die, so there is a motivation there to go out and get food (i.e. other species), among other resources from the environment specific to their capabilities.

There is no free lunch.

BUT species don't necessarily have to exchange resources with others to live in their habitat. They might need to defend it from other organisms of their same species or of other species, or they can share it with those. Exchange relationships can also arise, but they aren't necessary to happen.

Habitat can of course degrade over time, so there is a motivation to maintain and repair that habitat or move to a more suitable one nearby or far away.

This is all to say that humans, the exceptional beings we are at solving problems and doing amazing things, should be able to invent ways to get around entropy and inconvenience, which we have to a degree: not perfectly, though.

Regarding this article, I'm not sure I want people to own land for the sake of "owning". Perhaps a case can be made where people who use the land apportioned to them get to keep it over time (see what the Nordic countries are doing). This would exclude land and homes people have in other states or countries.

Not sure what the other consequences of this practice are tho, so I welcome any feedback anyone might have