We could make that assumption or make the assumption that more precautions would have allowed these plants to stay open. At this point, it's all guessing. What we do know is doing nothing resulted in these plants being closed down.
Do we know that they didn't do anything different than they had been? I also work for a meat production plant. We are putting temporary barriers between employees(because in our situation you can't just space them out due to the way the building functions), our breaks have always been staggered, shift changes have been changed to have reduced contact, office workers are work from home when possible.
We still are trying to get masks, which due to shortages is almost impossible. Nitrile gloves are a requirement in some parts of the facility and are not allowed in others because if they come apart in the product they can't be detected by metal detectors and in some instances x-ray, so cotton gloves are worn in those parts of the plant.
All this boils down to even if we have it spread through our plant is anyone going to be like you and just assume that nothing was done? Yes they made some big mistakes, but that doesn't mean that there were not some mitigation efforts in place.