I think you are seriously underestimating the impacts that worldwide crop failures in the next 20 years are going to have as far as global human catastrophes go.
The higher price for food will cause millions of deaths, an impact comparable to COVID or to the Ukraine and Ethiopian wars combined. It will pale in comparison to the impact of WW2, the black plague or the Chinese cultural revolution.
I like my phrasing "millions will die". That works on numerate people, but most people can't really conceptualize the difference between a million and a billion. Any other suggestions?
Do you have any genuine studies that show such impactful effects?
I'd almost bet money on the eventual use of stratospheric sulfide injection to cool the planet. It's cheap enough that even a third world country could conceivably pay for it. We have no idea what the side effects will be, but it may well be worth the risk to avoid 3-4c of warming.
The amount of arable land that will be lost in the tropics is going to dramatically impact all countries around the Equator. Some areas simply will not support human life without air conditioning with a 2 degree increase in wet bulb temperature and +3C increase in extreme weather events.
Crop failures are linked to many historically extreme events. A 15%-30% in staple foods has _massive_ impacts in the poorest 20% of the population. In poor democracies it leads to people voting for demagogues and autocrats; in other places it's much worse.
The cascade of these events with ever increasing temperature is exponential.
Some crops like coffee, chocolate and grapes are going to see an extremely dramatic reduction in arable surface