In Fahrenheit 451, is the society to blame for where they are now?
I would say that the society of the time of the book is partly responsible for where they are now. The society of earlier days (when you sort of add all the earlier days together) is more responsible.
The society has gotten to where it is right now because of the actions and inaction of just about all the people who have lived in that society since around the time of the Civil War. Everyone is responsible because everyone has participated in giving in. Everyone is society (except for a very few people like the McClellans or Granger and the book covers) has gone along with the way things are. They have not fought back.
No one generation was responsible for the way things are "now." Instead, each generation helped to create the situation. The situation was in place by the time the current generation was born, which is why I say the older generations are more responsible. But the current generation has helped keep things the way they are and so they are responsible too.