This is pretty funny, and the possible spoilers are vague enough that even if you're not caught up through the last season of Game of Thrones they probably won't hurt your enjoyment of the series when you get around to it.
I quite enjoyed watching this, but I can't let it pass without some griping.
First, it presents in passing a commonplace but serious misconception about how Social Security is designed to work and predictably mislabels it a "Ponzi scheme." I wrote a post debunking such misconceptions back in 2012 and multiple other posts on the same general topic over the years, so I won't rehash it now.
The video also misleads with respect to the national debt. Debt can certainly be a problem, but it can also be useful when servicing it is affordable and the borrowed sum is spent responsibly on things that save or make money. That's why businesses, individuals, and governments routinely borrow, as any self-respecting pro-business Libertarian really ought to know.
In passing, I like to remind people that the last two presidents to balance the federal budget were Bill Clinton and Lyndon Johnson. Johnson did it at the height of the War in Vietnam, the War on Poverty, and the Apollo Moon program, and Clinton ran surpluses so large during his second term that the national debt was on track to be paid off in a decade or so. In fact, thanks in part to economic growth, almost every president since World War II, from Harry Truman through Barack Obama, reduced the ratio of debt to gross domestic product. The exceptions were Gerald Ford (who held it pretty much steady during his relatively brief time in office) and Ronald Reagan and the two Bushes (who greatly increased it). Look it up.
Finally, I respectfully -- well, not that respectfully -- disagree with the notion that Libertarians advocate maximum individual liberty. My enthusiasm for individual liberty is the reason I'm not a Libertarian. The core fallacy of big-L Libertarianism is the notion that the only threats to liberty come from the government and those who use physical force. Would that things were so simple! This is the view taken to extremes by notorious crank Ayn Rand and the adolescents who haven't outgrown her. (To be fair, most serious Libertarians I know try to distance themselves from Randian extremes. The head of my state's Libertarian Party once told me over lunch that the hardest thing about being a Libertarian was having to deal with Ayn Rand nuts.)