"Wealth used to be based on land and natural resources, true, but this was proven to be wrong by the late 1600s."
I don't think that such a thing can possibly be "proven" to be wrong. In fact, the economist Henry George in his book "Progress and Poverty" makes a very compelling argument which suggests that monopolization of land and resources is the fundamental mechanism by which vast disparities in wealth are created and perpetuated.
Condensing his arguments here would be impossible, but basically, if the rules of your society prevent you from accessing land and resources, you are automatically deprived of the ability to lead a self-determined and "free" existence. If you have no access to land or resources, you have no access to shelter, no way to grow food, hunt game, raise animals, etc. In the extreme case of resource privatization, you would have no access to air or water. George therefore argues for a system which levies taxes on land and resources as opposed to one that taxes productive activity.
It makes sense to me because the amount of land is fixed, so unlike taxing income, you don't create a dis-incentive for engaging in productive activity. I think the ideal public policy would be one based on a hybridization of the Austrian and George theories of economics, applied in the context of a limited Constitutional government.