> In 1970, a single minimum wage income can raise a family and save up for extra.

My memory seems to think that wasn't true.

However, there were a ton of manufacturing and manual labor jobs that were capable of supporting a small family and they didn't need a college degree.

So, you had most young people earning positive money for four years at a very biologically fertile age rather than going into soul crushing debt at that age.

  Then I got Mary pregnant
  And, man, that was all she wrote
  And for my nineteenth birthday I got a union card and a wedding coat

Bruce Springsteen -- "The River" -- which was apparently a fictionalization of his brother-in-law