WE DON'T have the machines! John Deere and Case and AGCO and Claas have the machines. What open source non-profit modern machines are there out there you're talking about? Because I'd love to buy one.
Also, no one is incentivized to throw food away, people are lazy AF and rich westerners somehow don't seem to mind waste. Don't attribute to malevolence what incompetence will explain.
I used to live in a place that was at the bottom of the UNDP development scale. When I would go "out" to eat basic rice and sauce, I would usually have 2-6 kids, like actual children, standing next to me waiting to eat the scraps. And they would fight over a few handfulls of rice because they were starving and that was the system of alms-giving. And while I feel guilt now for every bite of food I waste, and I try not to, I'm not about to expend 200 times the energy to DHL cooked rice to West Africa. You have to balance resource use at a local level with the resources needed to move food other places. Even shipping all that soy that China didn't buy from the US to anywhere in need incurs huge costs, plus significant CO2 emissions.