Overall, it is neglected knowledge just how much the “Green Revolution” has slowed down since the 1990s. In Africa, measured heights have stagnated or declined in recent times. Robert Paarlberg’s Starved for Science: How Biotechnology is Being Kept Out of Africa is an excellent book on its title topic and more generally on falling TFP in global agriculture.
On other commodities, there are further charts and graphs (on both sides of the debate) here. The article is overwrought but worth the read, as it shows how far we are currently from the world of Julian Simon.