The article doesn't give an explicit answer to why food production has gone down, but it alludes some reasons for it. - Prioritizing on cash crops (corn, soy)

The article doesn't give an explicit answer to why food production has gone down, but it alludes some reasons for it. - Prioritizing on cash crops (corn, soy) instead of the traditional nutrient-rich crops which are more suited for the region - Furthermore, the reduction of crop diversity might have lead to worsening of soil conditions - Force-selling expensive equipment and materials (hybrid seeds, synthetic fertilizers) made farmers fall into debt, which could lead to a contraction of the farmer workforce Although there needs to be a much more thorough study than this article to get the bigger picture, I think the main issue here is hamfisting American ways of mechanized farming to African land. With different soil, climate, and socialeconomic conditions, blindly modernizing agriculture might just not work on Africa.