If the category you are working with is the kind of thing that you have to construct such nuance, and circles, and "yes but also..."s around, perhaps you might question your category outright?
Just to say, have you ever maybe thought that what we call "intelligence" is somewhat determined more by time and place than it is by our collective answers to multiple choice questions? Just maybe something to think about.
What you are describing is the difference between a Nicolai Tesla and a Thomas Edison - Tesla was far more brilliant than Edison and what he's was doing was superior to what Edison was doing in the same field of study but Edison won and Tesla died poor and most of his greatest discoveries died with him.
The world is not made for smart people - like I said, an IQ of 150 is an incredible obstacle to a normal life. That is relevant. IQ alone is not enough but of someone spends a lifetime living with a high IQ and paying my sort of attention they will see connections that others don't, stuff will just be obvious to them that others cannot see at all, stuff that others lose sleep over won't bother them and what causes them to lose sleep others won't understand.
I think you need to think further in your thought process if you think something so substantial is merely a consequence of time and place - I assure you there is more to it.
Now a little bit cheekier advice. Let me help you make an argument for your position against someone like me, because I really didn't see how I was to be convinced that this thing we are talking about is "substantial" enough to reduce any which way. The only way you can really argue with my position here is to take the point of view that "intelligence" is something like a metaphysical category. It doesn't have to be exactly that, but the important thing is that intelligence is more something "justice" than it is like "phenotype" or "language" or "neuron". You simply cannot be a materialist and also hold the fundamental nature of something like "intelligence," I wont insult you by filling in the dots there, but just know you are committed to a bit of woo-woo when you want to go all the way like you are (which is fine, I like woo-woo, just not in this case). You want, at the end of the day, for the brain to be more than an organ, but a truly teleological entity, which by chance has now touched upon something "substantial". Its a rough argument to make these days, you would of done great in the Enlightenment though :).
Also, what I believe you were trying to get at with the Tesla/Edison thing is this idea that Edison manifests my point of view because he was more successful in like the capitalist sense than Tesla. But that is just surface level here, and not at all what I am saying. I would come back and say "no, those are simply too people we are now calling intelligent, for different reasons." Intelligence isnt about results, its about certain things that we value (at a given time). And I am not quite sure even how you want to make your point here, we all generally consider Tesla as a very intelligent man these days, people even did back then!