If we are efficient enough in our use of land, the demand relative to the supply will shrink enough that it's no longer scarce.

I suppose lots of people enjoy owning their own land-- large tracts of it in fact, and not sharing it with anyone. That's a little tougher to conceptualize as post-scarcity as there's a limit to making land enjoyment more efficient with advanced technology. But in a world where other resources are less scarce perhaps we can think about colonizing other planets and terraforming as ways to increase supply.