Scientific progress, economic growth and civilization in general are proportional to the number of intelligent people and inversely proportional to the number of not-so-smart people.

That seems a little bit simplistic. How many problems have been caused by smart people attempting to implement plans which seem theoretically sound, but fail catastrophically in practice? The not-so-smart people are not inclined to come up with such plans in the first place. In my view, the people inclined to cause the greatest problems are the smart ones who are certain that they are right, particularly when they have the ability to convince other smart people that they are right, even when the empirical evidence does not seem to support their claims.

While people may not agree with me on this, I find the theory of "rational addiction" within contemporary economics to carry many of the hallmarks of this way of thinking. It is mathematically justified using impressively complex models and selective post-hoc definitions of terms and makes a number of empirically unfalsifiable claims. You would have to be fairly intelligent to be persuaded by the mathematical models in the first place, but that doesn't make it right.

basically, my point is: it is better to have to deal with not-so-smart irrational people than it is to deal with intelligent and persuasive people who are not very rational. The problems caused by the former are lesser in scale.