Presumably they are referring to the reduction in average quality that came with scale and cost related changes in food production. If you buy (expensive) eggs

Presumably they are referring to the reduction in average quality that came with scale and cost related changes in food production. If you buy (expensive) eggs from a small farm, they objectively taste better than eggs from a cheap or even average grocery store. My impression is that whatever “innovations” produce this difference had not yet been put in place 50 years ago.