Why is this an issue for China anymore than the West?
In fact, China has the majority of the world's grain stash. https://asia.nikkei.com/Spotlight/Datawatch/China-hoards-ove...
https://impact.economist.com/sustainability/project/food-sec...
The US ranks 9th whereas china ranks 34th. They're not going to famine or anything but food prices, or really just inflation more broadly, could be an issue. The reason china stockpiles grain is because it doesn't produce enough for itself.
The same logical structured can be applied to not China:
"X country's biggest problem is ... food availability due to lower exports of wheat from russia and ukraine could cause an issue too."
Calories/per resident? There's many ways in which that is flawed.
https://impact.economist.com/sustainability/project/food-sec...