I believe most of what ails us is being driven by demographic changes. Student loans, lower interest rates, and student debt is a prime example.
First, note that as the Fed has driven rates lower, universities and students have responded to the cheaper credit by taking on greater debt (chart below).
Next, notice the US Census estimates for the population growth among the US college age population (18-24yr/olds). The chart below is the population estimates from the Census prior to and after the 2010 Census. A steadily growing population among the college age population over previous decades came to a halt...and the Census sees no growth among this population for at least the next 20 years. With interest rates on the rise (lol) and a flat to declining population of students...perhaps the situation is far worse than acknowledged or understood?
And just in case you're unsure of how significant the demographic challenges we are facing are, review the below charts showing the near stall of the 0-5yr/old population vs. the soaring 75+yr/old population. These are not %'s but total populations. Without the population growth, there will not be adequate economic growth to pay down or even service the huge debt loads.
And the last chart again shows the 0-5yr/old global population vs. the 75+yr/old global population. This is not simply a student loan or US debt problem...not even an advanced nation issue. This is global and student loan debt is simply another symptom of the much deeper issue we seem unwilling to face.