The reason you don't see me arguing against your specific example is not because I agree with you in principle, but because I know very little about Latin America. I've read - most particularly in Hernando de Soto's writings, who is a Latin American intellectual of great standing - that the problem there is not so much the lack of property in the hands of the poor, but the lack of proper mechanisms of property enforcement and property recording. For example, the poor in third-world states own de-facto up to 11-15 trillion dollars' worth of stuff between them, but because a lot of that ownership is informal - for example, poor people owning homes but not holding formal 'title' on them for whatever reason, they're unable to leverage that into financial success.
I am not sure that is true, however.
Sounds to me that you (or rather, de Soto) implicitly argue that the basic institutions of Western (Classical) Liberal Civilization (rule of law, contract law, property rights, free markets, etc.) are prerequisites for any chance at attenuating(1) the profound inequalities found in places like Brazil, Saudi Arabia, etc.
A sound argument, IMO.
Such institutions never developed in some places. When everyone was suck-*expletive deleted*ss poor, all were equally so. When oil, resources, or something else was discovered, the lack of such institutions naturally result in a few making good, while the vast majority remain in a "suck-*expletive deleted*ss poor" state.
Running with the premise above, is the erosion of the basic institutions of Western (Classical) Liberal Civilization partly/mostly/wholly to blame for the growing economic and social inequality in America? For example, rule of law being supplanted by rule of (wo)men ["Are you serious?" says Nancy Pelosi; not enforcing immigration law; activist judges], contract law eroding, gov't intrusion into the market, and all the rest.
I find it ironic that the very erosion sought by progressives is partly responsible for the inequality they claim to deplore.
(1) Attenuate rather than eliminate. Complete elimination of any of society's ills usually entails unintended consequences much graver than the ill itself.