Potatoes? I just think they’re neat!

Disclaimer: I do know the potato didn’t replace grain and instead was an additional food to be grown alongside grain on fields otherwise left fallow. It was actually the combination of potato farming and grain farming that led to the population growth. 
But all of this is far too subtle to put into a meme, so I’ll have to leave that for the context.

 

Context: The introduction of the potato to Europe changed the demographics of the whole continent.

Before this the most important staple foods were various types of grain. Grain is more difficult to harvest than potatoes: it has a smaller harvest window, first the stalks have to be cut when turning brown. Then the farmer needs to separate the husks from the stalks by treshing. And then separate the grain from the chaff by winnowing. And then all of that needed to be stored in a granary which was often an elevated building so that mice and rats didn’t get into the food supply.  
Grain also has less types of soil on which it grows well. And in a war those fields were sometimes burned down to deny the other army any food by looting the area.

In contrast the potato was much easier to grow: just put the tubers into the ground, dig them up when ready and eat them. It has a high calorie value and can be planted on a lot of types of soil including mountainous or swampy soil for example. 
This meant that fields that had to be left fallow every other year didn’t have downtime anymore but could be alternated between grain and potatoes. This lead to the potential useable area of agricultural land suddenly growing by a lot, in some areas even effectively doubling. 
Potatoes were also far less vulnerable to burning or looting by armies looking to deny supplies to the opponent. So your average farmer suddenly didn’t run the risk of starving when a war was being fought nearby, they could just rely on their potatoes to survive.

All of this had a very big effect on the demographics in Europe. More northern lands that were difficult to farm before could now produce a whole lot more. And that led to a very significant population growth, more in northern Europe than in southern Europe.

Frederick the Great of Prussia was a big proponent of potatoes and tried to promote their cultivation. 
It even goes as far that there’s a myth about him placing royal guards along the edge of his palace garden where he had potatoes. And then forbidding people from eating those potatoes, thus using reverse psychology to get the people to steal them and so spreading them across Prussia. 
This is a historical myth and didn’t happen, but it’s so widespread that people leave raw potatoes on his grave and the gift shop there sells potato merchandise.

I’ve heard the theory that you cannot invent (as in: create from scratch) the state if your agriculture is based on potatoes. Simply because the peasants can just tell whoever wants them to knock themselves out harvesting the things themselves. So the progression bandit -> goon -> tax collector cannot get started.

It sounds sorta plausible, but also a bit too funny to be actually true. Is there something to this?