I think another reason the self-styled élites are so frightened of artificial general/super intelligence is that they have spent the better (actually worse) part of a century convincing themselves and indoctrinating others at the pain of career-ending ostracism that “intelligence doesn’t matter” and that “IQ only measures how people perform on IQ tests”. But like so many of the objectively false things they profess to believe (“gender is a social construct”, “inflation is due to greedy capitalists”, “private gun ownership increases crime rates”, etc.), they know it isn’t really so and rightly fear being found out and falsified by means they cannot control through censorship and intimidation.
To the extent they profess that intelligence doesn’t matter and that unlike all other characteristics in which human individuals vary within a population, cognitive capacity is absolutely identical among all healthy members of the human species, then the only way to distinguish those who should rule from those they rule is that the former have credentials conferred upon them by élite institutions, managing to get more votes than the other guy, or being appointed to a position by an existing member of the ruling class so that their inferiors address them as “The Honourable” or some other term of submission. (This also explains why they believe that simply placing savages, descended from hundreds of generations of savages, upon the “magic dirt” of a developed country will transform them into people who behave like Swedes or [post-1945] Japanese, or that admitting them to Harvard or Oxford will transmute them into contenders for the Nobel prize, or that a country which is deliberately reducing its mean IQ from around 100 downward toward 90 can compete with countries with mean IQ of 105.)
As long as the variance in intelligence is relatively small, manifest mostly in the fraction of the population on the tails of the normal distribution, this fantasy can be maintained. But once you have a population with, not “superintelligence” but just, say, a mean IQ of 160, then the pretensions of the ruling class will be shattered and they’ll be shown up as the frauds they are and, even worse to them, people will be inclined to listen to whose who make more sense and are congruent with objective reality instead of the fantasies spun by The Honourable This, Doctor That, and Professor Whatshisname. This risks wrecking their whole racket of importing a dependent underclass to reliably keep them in power and do what they are told.
Imagine, for example, a browser plug-in which, unlike my OldSpeak script which merely mocks establishment media, annotates news and opinion articles and pronouncements by politicians and other authority figures pointing out factual errors, logical inconsistencies, flaws in reasoning, and appeal to emotion, with each linked to primary sources the reader could follow-up. The power of such a tool is acknowledged already by the usual suspects trying to deploy “fact checkers” against those who oppose them or they fear, but just imagine if their facts were actually checked on a continuous basis and refuted with citations.