Either time, 1970 or 2017, the number of university graduates is being limited, as the establishment has limited the number of med school graduates.
  In 1970, it was only 15% graduates because of lack of money and as you say not a necessity. In 2017, it's about 52% graduates also due to lack of money for many due to increases in tuition, despite a degree being a necessity. 
   My point is the determinant isn't a stable two parent family, it's having the money or not.
    In the US, conservatives love to blame all the problems African-Americans have succeeding on lack of stable families; similarly here with indigenous people and by extension, all those who cannot afford university. It's a reductionist fallacious argument, patently wrong.