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The problem with speculative fiction is that if you postulate a future society with too much change, your readers of today won't connect with the story—it may be too alien to deal with.

I agree with you on that point, but lets take another one of his stories. A man discovers after a vehicular accident that he is not really a man after all, but a sort of cyborg with human skin and blood outside, mechanical parts inside. He's an "Electric Ant."

While attempting to determine how his programming works he discovers a tiny device inside that controls his "reality". Everything he sees or experiences is being read off the device and interpreted by his mechanical senses.

Now, the device he finds inside himself is indeed a punched tape reel. But, Dick does take it farther by making the device so small that it can only be manipulated by a powerful magnifying apparatus and specialized tools wielded by robotic arms. Technology that didn't exist when the story was written, but that are familiar enough for his contemporaries to understand.

My beef with his use of the typewriter and carbon paper is that he didn't advance that technology an inch. Why didn't he use the understood technology of dictation and instead dictate the letter to a computer or robot so that it could make copies of the letter?

Maybe he just couldn't picture the ubiquity of today's computers to the point where we all have several in our homes available to us at any time.

I shouldn't complain though. The focus of his stories are usually on the manipulation of reality with the future and new technologies just setting the stage.