Personal responsibility for overspending plays into it, no one can question that. But people making, on average, less actual money than they made in the 60s is a sign of the inherent fallacies of trickle-down: it absolutely does not trickle down. It stops at the nearest corrupt executive, of which there are plenty.
Couple that with modern sub/urban realities. Many, many more people now have to drive to work than did in previous decades. They have no choice, because affordable housing is distant from their place of work. So now, they have the added required expense of a vehicle, in addition to the fact that they are actually making less money than they would have back when a personal vehicle wasn't as necessary. This leads to an inherent deficit. Even old cars are barely a better option, because repairs are so expensive that they can quickly make up the difference in cost.
As an example, though thankfully in my case I managed to get a good education and a well-paying job so I'm not financially at-risk: my job is 40 miles away from my home. Those 40 miles cost a significant amount in gas and vehicle repairs. But it's still less than the cost of living there. Here, my current rent (combined total with all residents) gets one side of a duplex with two bedrooms, two bathrooms, outside storage area, a yard and everything. That same total rent, 40 miles away in the city, gets you a studio apartment with one bed, one bath, and that's it.
Part of the reason we are now moving more towards government taking care of things is because of private industries' overwhelming failure to do so, and in some cases willingness to capitalize on the problem. Personal debt is a huge problem in the nation right now, and very, very few people can say they are debt-free. Everyone is well aware of all the bull**** credit card offers these days with some absurdly low introductory APR that then jacks through the roof. Credit card companies (and I'm talking major, respectable ones) have even started sending me "ACT NOW PRE-APPROVED BUY OUR ****" credit cards in unmarked envelopes to disguise who they are. These are large, flat grey envelopes with only my name/address on them, and inside is the latest mastercard offer.
Healthcare reform is a big topic these days. Oh noes, government healthcare is bad! This may be so, but how much worse is it than when my mother spends one night in a hospital for a sudden collapse, does one simple blood test, and the bill comes back in five figures? Fortunately she works two jobs and both have insurance, and the combined total covered it. Many don't have that luxury, and being hit with that sort of bill can absolutely be ruinous. Private industry has completely and utterly failed to provide acceptable healthcare.
I hold industry responsible for making a shameless attempt to get people in debt, profit off of the interest payments until they inevitably default, and then repo the assets to recover the initial outlay. It is predatory, and it should be criminal.
Are people responsible for taking the bait? Of course. But there are those who simply say "caveat emptor" and make no attempt to assign any blame to the loan sharks making the bad offers. They are just as culpable.