On the whole, my many years of research on substance use has taught me a major overarching lesson: we are much more likely to demonize drugs for their negative effects than consider their neutral or potentially positive impacts. Or -- in scientific terms -- there is a built-in bias in the scientific literature, textbooks, and popular press towards highlighting the negative aspects of drug use.
The IQ swindle is just this: an attempt to quantify the unquantifiable. The field aspires to the level of science, therefore it has to boast precision. It attempts to achieve this, disastrously, by counting something that can't be counted. By measuring something that isn't even, when looked at closely, a thing. The IQ scientists, at their worst, force their wretched notions to become facts.