There's no particular hidden agenda behind this title. What you see is pretty much what you get. Dickens looked out at the England of his day, where poor people were living in (you guessed it) really hard times. Many of them worked sad factory jobs, with strict bosses who forced them to work as hard as possible for very little money. Doesn't sound like too much fun to us. Dickens just he called it like he saw it. They were indeed hard times.