Obviously, you can have a university degree or two and still be completely incapable. You can be without one and be absolutely up for many jobs. Still, I find this map very telling: it is about what Latin American presidents studied after school.
Bolivia's president came from a very poor background in South America's poorest country and only visited a basic school. Uruguay's and Nicaragua's presidents studied law but left prematurely as they went to fight with the guerrilla. The president of Paraguay studied to be a Catholic priest and also to become the literal "father" of a nation (two children are linked to him so far). The countries you see in the map in pink have heads of state who did law. Those in brown and red studied politics and literature respectively. The one in blue studied engineering. The ones in yellow have presidents who studied economics. Lastly, the ones in green have heads of state who have a purely military background. Raúl basically learnt to fight with his brother. Venezuela's president went to the usual Military Academy for those who do not want to study much and he then abandoned a "postgraduate study" in political science" at the USB. I simply cannot understand how he was allowed to start it or even finish secondary school if he can say something like this: "mankind is 20 centuries old".