I never attended a university until much later in life. I was, however, pretty highly educated by the time I got there because I never stopped reading. I joined the library and read on every conceivable topic. This cost me nothing but my time. This is available to most people.

I have no idea why people are illiterate. We all learn to read in the first two years of school. It's not rocket science. I think this has something to do with the education system - not sure.