That's partially addressed in the comment I'd linked to above from an earlier post.
Not all oil is equal. The single-strike wells of the Persian Gulf which poured fourth 70,000 barrels of oil per day of light sweet crude, and are still producing nearly a century later (see the First Oil Well of Bahrain for example) are quite different from the lower-grade, hard-to-pump crude Venezuela has, or the production profile of a hydrofracked well.
Put simply, you want to consider the net costs of production, including the energy costs of production (EROEI -- energy returned on energy input) which are considerable for Venzuela. Also, incidentally, for the "largest ever" onshore US discovery of Texas shale oil announced a week or so back.
For Texas, the average per-well extraction is 20 barrels/day. These low-production wells are known as "stripper wells", and operators will literally turn on and off the pumps in response to the price of oil if it exceeds their ongoing production costs -- fuel or electricity for the pump jack, plus depreciation.
http://oilpro.com/q/1775/many-barrels-oil-does-well-produce-...
I don't have a per-well production statistic for Venezuela, though national production has held steady at about 2.5 mbpd since 2004.
http://www.indexmundi.com/energy/?country=ve&product=oil&gra...
There are a few end-run oil exporter scenarios. One, the "export land model" by Jeffrey Brown looks at the total domestic consumption of exporting countries, and sees a tipping point where domestic demand accounts for all production.
There's another scenario, in which the total financial accounts of an exporter are taken into account. Here, the problem is that when the global oil price falls below the costs of production in a country, it literally cannot afford to pump oil from the ground, and finds itself deprived of foreign cash flows. The classic case of this is the Soviet Union in the 1980s. Having based its national budget on the high price of oil in the 1970s, it was caught in the double bind of large flows of new fields (North Sea and Alaskan North Slope), as well as a plummeting global oil price with the 1980s supply glut. As much as anything, Saudi Arabia defeated the Soviet Union.
That story's been played out in several Arabian states, including Egypt and Syria (both minor oil producers), Yemen, Lybia, Tunisia, and, yes, Venezuela. Texas, North Dakota, and Alberta, Canada are all running into the problem of development predicated on $100/bbl oil in a world of $45/bbl WTI.
I don't care what your governmental or economic system is. If you're basing your economy on massive sales of extractive resources and the price falls out from under you, you're sunk.
Saudi Arabia has been making very interesting noises about its finances for the past few years. Keep in mind that KSA are essentially a family-run state / business. The House of Saud runs the country and owns the country's largest company, Saudi Aramco, accounting for over half the country's GDP. I'm not sure exactly what you'd call a state in which a single unitary power bloc controls the major economic unit, but it doesn't strike me as terribly democratic-market-capitalist.
I've also poked around the Heritage Foundation's Index of Economic Freedom and measures of per-capita wealth, to find some interesting bits. Dig around https://dredmorbius.reddit.com for more on that.
Again: the heated rhetoric tends to cloud more than clarify understanding of what's going on here. I say that without either defending or denegrating Venezuela. I'm simply interested in understanding it.
http://www.ibtimes.com/saudi-arabias-2016-budget-creates-new...