You're assuming that intelligence is a one-dimensional scale from dumb to smart. Actually, there are many different ways in which people can excel (or be deficient) cognitively, which most would agree makes them forms of intelligence. (Rather than through physical strength, which I can accept is not an "intelligence".)

A mention of the theory of multiple intelligences belongs here.

https://en.wikipedia.org/wiki/Theory_of_multiple_intelligenc...

Many of the intelligences are things that have very evidently contributed to our collective heritage of beautiful, rich and diverse culture: "musical–rhythmic, visual–spatial, verbal–linguistic, logical–mathematical, bodily–kinesthetic, interpersonal, intrapersonal, and naturalistic".

The cartoon version of intelligent humanity as Homo Economicus that you invoke is kind of missing the point, IMO.