As inflation-adjusted GDP approaches infinity the value of potatoes must approach zero, yes. Of course, were demand for potatoes to suddenly increase, the value

As inflation-adjusted GDP approaches infinity the value of potatoes must approach zero, yes. Of course, were demand for potatoes to suddenly increase, the value of potatoes would too, so it does not imply any ability to buy an earth-sized ball of potatoes for a dollar in the near future. But the price of potatoes, at typical demand, must approach zero, yes. The value of potatoes have been going towards zero for a long time, anyway. It's not hard to envisage a future with self-maintaining automated farming and fusion energy where potatoes are basically free.