There's an elitist way of criticizing social democracy that frames policies for the common people as ill-considered and destructive; you've been exposed to it any time you've heard the phrase "irresponsible populism." This phrase is most often used by conservative and centrist/technocrat pundits, but also sometimes by reasonable-sounding economists and financial analysts, and all of them are trying to make it sound like public programs go against objective economic science. In reality, the trope is a weapon to target programs and institutions that benefit common people instead of the wealthy, so that the wealthy can protect their privilege.
One point of clarification to start: currently, the term “populism” is sometimes used to refer to a politics of race-baiting, especially in reference to the xenophobic, Islamophobic, anti-Semitic, and racist parties of the far right gaining ground in Europe in the wake of the economic crash. But what I’m talking about here is “economic populism,” which is a subtly derogatory term used to describe traditional center-left welfare state policies and programs from unemployment insurance to public pensions. On substantive policy there is no logical connection between ultra-nationalist racism and social democracy (although sometime far-right parties support such programs when they can use them to intensify nationalist sentiments). But elitist rhetoric, I think, exploits the term “populism” to falsely imply connections between these two very contrasting agendas of the right and left. I supposed elites perceive both as ideologies supported by the lazy losers of the capitalism’s economic game, who they see as casting about for scapegoats and easy solutions rather than knuckling down and earning their money as proper people do.
Often, the premise behind criticisms is that public programs that benefit large numbers of regular people cost too much, and indeed are in principle unaffordable under any conditions, and therefore must be eliminated or kept at minimal levels. Spending too much on them, the argument goes, would tax the treasury beyond its limits, cause excess debt, and bankrupt the government. Of course, the billions spent on subsidies and tax breaks for corporations and the wealthy are never criticized in the same manner.
The trope is quite old, as this Charles Krauthammer piece from twenty-five years ago shows, with its claims from a conservative supporter of the Reagan Revolution -- which exploded the debt! -- that liberal policies will balloon the deficit until “the budget is hopelessly busted.” Recently some on the left have pointed to the increasing influence and popularity of liberal populism as people become disillusioned with centrist and conservative privileging of markets, followed by a predictable backlash from the right.
Populism is only irresponsible by the lights of failed right-wing economic ideology: conservatives believe the mistaken theory that too much government spending, rather than too little revenue from the wealthy, is the primary cause of government debt. The chart below from the Center on Budgeting and Policy Priorities (which is been circulating in different forms around the Internet for several years) illustrates the proportion of the debt caused by wars, Bush's tax cuts for the wealthy, the lost economic growth caused by the Great Recession, and recovery measures. If the worry is public debt, top solutions include ending the wars and using public spending to prime the pump and restore economic growth; but the best solution is to raise taxes for the wealthy and make them pay their fair share until the debt is paid off in full.
The irresponsible populism trope, however, is designed to prevent exactly that latter solution. It is mainly a strategy to continue, and even intensify, the decades-long redistribution of society's shared economic production away from the working class to the upper-class. Of course, this only allows those who have become obscenely wealthy to expand their decadent standards of living while accelerating the increasing inequality and middle-class squeeze that began in the 1970s.