For whatever reason, the Spanish and Portuguese were just not that into education, or education in their colonies, compared to the British. The contrast in the eighteenth century between the number of universities, printing presses, and journals in the British North American colonies vs in the Spanish and Portuguese colonies is hard to believe.
So once officials were no longer sent out from Madrid and Lisbon, you had a situation in the new Latin American countries where even the elites were pretty ignorant. That is one reason why monarchism was thought of as a reasonable political option, the argument was that there were not enough educated people to make republics successful and the historical record supports this.
There is one issue that I can think of that can't be overcome, and that is an issue that affects sub Saharan Africa, and that is that South America is somewhat geographically isolated. The development of Latin America is often negatively compared to that of late twentieth century Southeast Asia, but Southeast Asia sits literally where the world's major trade routes converge. Geographically, the closest continent to South America is Africa, and the geography of the continent is bad even for internal communication.