We live in a physical universe. So anything that makes one person more productive than another is physical. So it can be studied and copied.
We can study and copy access to resources, education, even genes.
So, if society chooses, everyone can perform at the same level as the best. But if a society chooses not to copy best practices, then that society will be weaker than it could be.
Ground rent simply increases efficiency. So the society that chooses more inequality will fail within a few decades, rather than over several centuries as now.