There are many momentous issues here.

First: I think a historical narrative can be constructed, according to which a future unexpected in, say, 1900 or even in 1950 slowly comes into view, and in which there are three stages characterized by an extra increment of knowledge. The first increment is cryonics, the second increment is nanotechnology, and the third increment is superintelligence. There is a highly selective view; if you were telling the history of futurist visions in general, you would need to include biotechnology, robotics, space travel, nuclear power, even aviation, and many other things.

In any case, among all the visions of the future that exist out there, there is definitely one consisting of cryonics + nanotechnology + superintelligence. Cryonics is a path from the present to the future, nanotechnology will make the material world as pliable as the bits in a computer, and superintelligence guided by some utility function will rule over all things.

Among the questions one might want answered:

1) Is this an accurate vision of the future?

2) Why is it that still so few people share this perspective?

3) Is that a situation which ought to be changed, and if so, how could it be changed?

Question 1 is by far the most discussed.

Question 2 is mostly pondered by the few people who have answered 'yes' to question 1, and usually psychological answers are given. I think that a certain type of historical thinking could go a long way towards answering question 2, but it would have to be carried out with care, intelligence, and a will to objectivity.

This is what I have in mind: You can find various histories of the world which cover the period from 1960. Most of them will not mention Ettinger's book, or Eric Drexler's, or any of the movements to which they gave rise. To find a history which notices any of that, you will have to specialize, e.g. to a history of American technological subcultures, or a history of 20th-century futurological enthusiasms. An overkill history-based causal approach to question 2 would have a causal model of world history since 1960, a causal model of those small domains in which Ettinger and Drexler's publications had some impact, and finally it would seek to understand why the causal processes of the second sort remained invisible on the scale of the first.

Question 3 is also, intrinsically, a question which will mostly be of interest to the small group who have already answered 'yes' to question 1.

A good illustration of multiple discovery (not strictly 'discovery' in this case, but anyway) too:

While Ettinger was the first, most articulate, and most scientifically credible person to argue the idea of cryonics,[citation needed] he was not the only one. In 1962, Evan Cooper had authored a manuscript entitled Immortality, Scientifically, Physically, Now under the pseudonym "N. Durhing".[8] Cooper's book contained the same argument as did Ettinger's, but it lacked both scientific and technical rigor and was not of publication quality.[citation needed]