There are two competing things going on in SA: farm yields are dropping significantly since the 90s because of the government racist land transfer policy.
Note that on one hand this is decried in the news media as a sign of ‘white privilege’, when land is transferred to unprepared black farmers and the massive government subsidies not being enough to sustain some 20-year old with a business college degree, a dream of but no experience in farming, simultaneously holding in other articles that race based land confiscation doesn’t actually happen.
However SA was a huge exporter across Africa both because similar policies in other countries killed their farms with communist/socialist policy generally ending in dictatorships and war. Now that supply is under pressure, prices skyrocket. So yes, they make more money off less food. That will be the case until they cannot sustain themselves anymore, which is fast approaching, with some areas already seeing food shortages.
On the other hand, the UN and even the US has pumped billions of dollars over the years to maintain the lie that the SA land transfer program has been a success, so the west (look up Gates and Soros foundations investments into ‘One Africa’) is investing in quick return products just to drive the SA government into more investment, which brings short term yields (anyone with a million dollar grant can get 1-2 years of intensive non-food crops like seed oils before the land becomes depleted) but long term damages.