Asimov's way of writing was very typewriter-centric, so maybe it's not surprising that he in particular would fail to imagine word processor-like technology:
Second Foundation also came out in 1949, before the stored-program computer was invented. Computers at the time were room-sized electromechanical devices used for codebreaking or artillery calculations; there were no more than a dozen or so in the world, the general population was unaware of them, they couldn't be used interactively, there were no plans to use them for text (a typical diary entry wouldn't have fit into the EDSAC's memory anyway), and the idea that a computer could fit in your pocket and let you edit anywhere within a document probably seemed stranger than the idea of spaceflight.
Science fiction seems to resonate strongest when it introduces new ideas which are reachable. Neal Stephenson’s Snow Crash seems to be particularly influencial. Sticking some plot line in the future isn’t enough.
I miss those moments I had when I was younger, reading Neuromancer, Snow Crash, and the Diamond Age for the very first time. Certainly they all played a driving role in orienting me toward what I ended up spending my life doing. The stories and the characters mattered, but the technology drowned it out.
https://en.wikipedia.org/wiki/Isaac_Asimov#Characteristics