Nobody forced the farmers to become reliant on migrant workers though. It was just a simple decision for them: cheap labor that's available today or expensive labor... They mostly went with cheap, and now they don't have anyone available. Tough luck I guess, but it always was just a question of time until this happened.
This is not about farming though: it's the canary in the coalmine for the entire economy.
You cannot just stop the economy and print magic money and expect everything to be ok.
We have to be smart like Koreans and control this virus effectively so we can progressively get some of the gears going again, because pain is coming otherwise.