I would think that Ray Bradbury would have hoped that everyone would read and understand this story. I think that because his message is that we need to get control of the technology that is threatening to control (and destroy) us.
I would think that his best hope for a target audience would have been relatively young adults. It would be this group that would have been more idealistic and likely to heed his message.
I would think that the older generation would have been more interested in getting their lives together and getting ahead after having lived through WWII and the Depression.