I think what is really going on is that is not 'fluid IQ', but regular, normal "IQ".
"Fluid" intelligence is the ability to think, reason, solve problems, and learn things. "Crystallized" intelligence is your amassed knowledge.
These are technical terms used in the literature.
Intelligence is nature's guess as to how complex your environment will be... but there's an out. People with low fluid intelligence have to work harder to understand things, but if they put in the work they can amass a body of knowledge that rivals that of people with high fluid intelligence.
And of course, lots of people with high intelligence stop learning in their mid twenties. At that point they've conquered their environment and are living successful lives (good job, married, kids &c) so there's no real reason to push themselves. Lots and lots of people, even smart people, haven't read a single book in the last year - and this observation was true in the 1970's before the internet.
(And nowadays this is probably more accurate due to the appalling quality of information found on the internet.)
That is, stupid people either do not realize the AI is wrong, or more likely, they are so used to being corrected by more intelligent people that they just assume the AI must be smarter than they are and do not challenge it.
It's a question of training. We're evolved to believe what people say, it's a way of reducing the cognitive load of learning things (by believing what someone else has already figured out). We're not used to questioning the logic of someone else's beliefs.
As an example of this, note that Warren Buffet has built a career on identifying fallacies in business, google "Warren Buffet fallacies" for a list.
None of these fallacies is taught in school, everyone has to find them and figure them out on their own. And then you have to use them in your daily lives.
Almost no one is used to doing that, which leads to the current problems with AI.
Shareholders are crying
Replace them with AI as well.
The claim that "false premises invalidate everything built on them" only holds when the error is unrecoverable and propagates non-linearly.
But in many cases:
The error is consistent and quantifiable, so results can be recalibrated
The relational findings survive even if absolute values shift
The direction of effect holds even if the magnitude is off
A good counterexample of this is carbon dating. Early carbon dating used an assumed atmospheric C-14 ratio that turned out to be slightly wrong. The premise was false, but scientists didn't throw out decades of dating results. Instead, they developed calibration curves (using tree rings, coral, etc.) to correct the systematic offset.
Another reason is that if you send someone up there for roughly a year just to get there
With a working fusion rocket you won't have to coast most of the way, and the journey can be significantly shorter. It's right there in the summary: "from months to just a few weeks". Though I doubt that this company will build an actual fusion rocket motor anytime soon, if ever.
The Wright Bothers weren't the first to fly. They were just the first not to crash.