It's generally true that the rarer something is the more valuable that is, but only if there are enough potential buyers of the thing that can recognize it. If there is an ever-decreasing amount of intelligence there is probably an ever-increasing amount of stupidity - so will the stupid be smart enough to reward the intelligent with high paid positions?
What I suppose is actually that human intelligence will become more monetizable, by allowing those with it to better take advantage of their unrecognizable ability. But only if the interlocking systems of humanity do not fall apart and destroy the world due to there not being enough intelligent people left to make things work, as per various works of science fiction on the subject.
That's the issue. No one can really systematize "discovery".
How many "group thinkers", "creatives", "non-group thinkers", "nihilists", "anarchists", "contemplatives" in the last - say, 500 years, 5000 years, whatever - have been occasioned by the fall of an Apple? Or the fall of a branch? Or a leaf? Or what have you?
Why did it spark a new flame in the mind of Newton? Science can't explain. If we could, we'd teach everyone to be that sort of contemplative.
The intern I worked with last year said her graduating class all felt like they were the last "real" graduates. Meaning: the class after her had less credibility in her eyes, having been presumed to have used AI to get past the "pons asinorum"/"bridge of asses".
On the one hand, one really can't remove all of humanity from the economy. Humans are what makes the economy matter, and if you cut them all out, they'll just replace the economy with something else, call it "the economy", and move on. ("Butlerian Jihad" pivot, I suppose.)
On the other hand... I'm reminded of dock workers and the advent of container ships. The only way to handle that was to basically pay those workers a living wage for the rest of their lives to ... not work.
So... we have options, I guess!
[1] In Orson Welles's Time Machine, the eloi were the lazy "child-like" humans not challenged to grow intellectually.