The fact that those countries supply raw materials to developed countries is necessary for the system to keep running. Because as long as those countries are exploited, developed countries can live in prosperity. Cocoa workers do not even earn as much as the price of one chocolate bar per day.
Limited knowledge and limited infrastructure to innovate and pressure from the system that was created, the price of raw materials is suppressed in such a way that farmers do not get returns that give them big profits, this does not happen to cocoa but other natural resources, such as mining both earth minerals and oil, developing countries only become suppliers of raw materials, then processed by producing countries and then returned with finished goods at a higher price, most developing countries are trapped by developed countries from the side of cooperation signed by corrupt officials in developing countries.