The mix of far-sight and backwardness you describe in (3) is common to a lot of sci-fi. I remember one book of Clarke's that describes a journalist taking a trip to the colony on Mars, and to write his articles he takes a portable typewriter with him. There are a lot of anachronisms in Asimov's early Foundation novels as well, such as many characters smoking, a total lack of computers and everything still being done by humans - taxi drivers, customs officers stamping passports, etc. I guess it's a pretty hard thing to see what parts of society are going to be replaced, especially given some of the disruptive technologies like computers that have popped up mostly after these books were written.
Couldn't (4) just represent a fairly good design for Multivac so asking it one hard question doesn't lock it up for everyone else?
I actually enjoy this mix of old and new in sci-fi, from an artistic viewpoint, that is. It gives it this little flavor that is a mix between very high technological advancement and simple nostalgia (obviously not intentional by the author, just a side effect of me reading this story in 2012). When I try to imagine a cool fictional cyberpunk future, I find it much more satisfying to picture hackers hacking away at the keyboard in front a screen filled with green text over black background than the more plausible shiny white touchscreen.
I prefer my space exploration to be done on a Nostromo than a Enterprise.
I consider this to be based on their idea, that scientific inventions will change humanity on large scale, like space travel, etc, and small things will not have time yet to catch up. While in reality small things change fast, and we are still missing large scale changes.
There is for example the Cyberpunk genre (starting from eighties) which predicts things much better. There are much less large scale inventions in that, and a lot of smaller, human life style changing things that were got right. Cyberpunk also started after the world took direction towards the current form of capitalism, and the utopian ideas originating from before sound strange today.
Funnily enough I do all my work on a teletype, using antiquated interfaces from the 70s, and secretly wish for a 40 year old keyboard to program my 30 year old programming language in.
Some anachronisms are not really anachronisms - they are just proofs of the fact that the old way was in some decisive way better.
Couldn't (4) just represent a fairly good design for Multivac so asking it one hard question doesn't lock it up for everyone else?