TL;DR : le Venezuela n'est absolument pas une preuve que le socialisme ne marche pas.
Le pays est bloqué dans un cycle austérité => croissance court terme => crise économique depuis plus de 50 ans, lié au fait que les gouvernements successifs misent tout sur le pétrole, depuis toujours. Et du coup quand une crise pétrolière se produit, toute l'économie se casse la gueule.
En parallèle, la Bolivie qui avait les mêmes cartes de départ que le Venezuela (économie basée sur le pétrole + gouvernement socialiste) s'en sort bien mieux, principalement parce qu'ils ont implémenté leurs propres programmes sociaux et diversifié leur économie, chose que le Venezuela n'a jamais fait.

"2/3 of the Venezuelan economy is privately owned.
70% of their GDP is generated by the private sector.
And as a result 80% of the workforce is employed by the private sector.
In fact, 2/3rd of Western Europe has more state employment than Venezuela does.
[...]
Before Chavez, poverty and wealth inequality was high, in the 1970s, the poorest fifth of the Venezuelan population had 3% of national income, while the wealthiest fifth had 54%. The presidency of Chavez initially brought about a great decrease in poverty- he solved the unemployment problem that plagued Venezuela for decades, increased literacy and doubled GDP per capita.
[...]
At one point, it was estimated that about 90% of the Venezuelan export revenue came from oil & gas. The Venezuelan government overspent in a lot of their projects and instead of using the oil money and the social programs It funded to diversify the economy and to grow it in the long run, Chavez kept implementing those policies without any foundation to back it up in case the oil money runs out.
And when the market got glutted and the oil prices crashed as a result of multiple countries raising output to drive each others out of the market. The exact same thing that Chavez feared happened, he was just not around to see it. All was left for Maduro, a former bus driver to handle and even he was not so good at driving this bus.
As you can see, none of this have anything to do with socialism whatsoever
[...]
But just like the current Venezuelan government had, the old Venezuelan government would soon learn that prosperity solely from oil can never last. And after the 1973 oil crisis, it became truer than ever, or as Juan Pablo Pérez Alfonzo(the Venezuelan responsible for the creation of OPEC, among other things) had noted:
"Ten years from now, twenty years from now, you will see, oil will bring us ruin... It is the devil's excrement."
And eventually it happened, during the 1980s, the oil prices collapsed, the economy contracted and inflation rose exponentially. You’re starting to see a pattern here right?
But that’s not all, responding to the volatile economic situation, the Venezuelan president Carlos Andres Perez took the classic road that all developing economies in crisis took during the 1980s, that is Austerity.
The allure of Austerity was too good to pass. And as a result, he accepted the Washington consensus in 1989 In exchange for $4.5 billion in loans intended to save his country.
And just like most countries that had implemented Austerity, it did not work.
[...]
Venezuela was stuck in a vicious cycle of:
Austerity → short-term growth → economic crisis.
[...]
I often see people criticizing Chavez stating:
"Before Chavez, we were the richest."
Well yeah, and then you got poor, because none of the growth before Chavez was sustainable and it was only a matter of time before everything collapsed, just as it did.
[...]
And another argument which I often face is people claiming:
"Venezuelan Socialist policies caused the economic crisis"
Before saying this, they should keep in mind that those same “Socialist” policies like price control or subsidies have been implemented in almost all countries in the world, developed or developing and most of them did not go through the same thing as the Venezuelan did, or let us look at nowhere further than the Venezuelan’s Socialist neighbor, Bolivia for example.
Since 2006, Bolivia has been run by a socialist party under Evo Morales, their economic policies were as every bit as militant as the Venezuelan. But Bolivia experienced sustained growth with an immense reduction in poverty, an inflation rate of 4% and shortages of consumer goods virtually does not exist.
How is that possible since they’re both Socialist and implemented the same set of policies? The twist is that the Bolivian implemented their own social programs and diversified their economy with that while the Venezuelan did not do so. Or just look further to Western Europe as another example.