In the past public opinion would be created by a minority of affluent people. Most people were basically peasants (even middle class with nice jobs) and had no chance to affect public opinion. Today public opinion is created by the majority (or manipulated by some shadowy figures with unknown agenda -- I can't make up my mind about it). So you could have more educated people today but still responsible for much smaller fraction of actual public message.
Also in the past the information that most people received was nicely prepared, packaged and delivered by more or less mainstream media. Clear signal, low noise. For better or worse.
Today truly educated and wise people have no access to public because the signal to noise ratio is too low for most people to be able to pick up.