I think this narrative of food-bowl control is so enticing to people who think about power that it becomes a self-fulfilling prophesy. "Everything is linked to control of food bowls!" People believe in it and then act on it, and only then does it become kind of accurate (apart from South America, and all those successful countries who don't have a food bowl). Russia, America, China could all decide at any time to sell things and just focus internally and they'd break the narrative further.
What you're describing is an evolutionarily stable strategy (ESS) [1]. If you've played the board game Risk you have an intuition for this prisoner's dilemma solution.
In Risk there are two tendencies that tend to emerge: everyone gets a continent or nobody gets a continent. In the former the player(s) who resist the ESS by not acquiring continents are left with diminished armies and quickly eliminated. In the latter the player(s) who resist the ESS by attempting to acquire continents are rapidly allied against by the others.
The ESS involves random psychology within the constraints of geopolitically fundamentally dictated equilibria. The agents, in this case nations, tend towards one of those equilibria by acting independently on limited information about others' intentions.
The dominant equilibrium then becomes a self-fulfilling prophecy, as you have observed. It does not follow, however, that there is no rational basis for the phenomenon. There is also no known mechanism outside a supranational authority with enforcement capability to force a shift from one equilibrium to another.
