From the perspective of the farmer re: natural resources and the capitalist re: human labor, they are precisely the same: an existing capability in the world that can be used to produce value that can be sold for more than that production costs.

Obviously when viewed from other perspectives, they differ significantly.

Understood, but you're removing the moral aspect of the capitalist's exploitation of labor from a discussion on why the capitalist gets to make a billion dollars and the farmer doesn't.