Smarter humans, not artificial intellegence

IQ testing is controversial in some ways but supported in others.

In support of IQ, some forms of IQ tests ('g' loaded tests) tend to reproduce similar scores for the same individual. Further, this score is linked to various life outcomes - higher numbers of patents created, higher academic success rates, higher income, less time in jail, etc. As well as all of this, IQ has been found to be hereditary through twin studies. Lots of literature on this suggest that whatever IQ measures, even if it's not intelligence, it's useful to have in western societies.

But here's why it's controversial: Firstly, there is a potential gender and racial bias. Certain races tend to do better than others on average even controlling for socioeconomic status and the like. Men tend to be at the extreme ends of the scale, with many more falling into the high scoring ranges (2+ standard deviations) than women as well as in the low scoring ranges. Secondly, langauge barriers are another large problem with any verbal-based IQ test, which restrict those tests ability to accurately gauge a test taker who is writing with English as their non-native tongue. Thirdly, there are arguments about how a single number could accurately represent all of human intelligence. In tangent with this, there is debate about what constitutes intelligence, and how we should group it. Should emotional intelligence count? Should physical (kinetic) intelligence count? Should math count as much as verbal? Should problem solving count? Etc.

Against the last point, ignoring the less traditional sorts of intelligence (e.g. kinetic [bodily movement] intelligence), 'g' loaded tests support the idea that even if you're bad at math, if you've got a high 'g' score you'll likely be above average at math if you're high above average in 'g' loaded verbal or logical reasoning tests. So it seems that even if you're deficient or exceptionally good at one area, there is some sort of underlying factor that does help explain at least some difference in the traditional realms. And that underlying factor is what 'g' loaded tests are supposed to assess.

Also worth noting is the decreasing returns after about the second deviation. Although it does continue to have increasing effects in some areas, benefits in other areas start to drop off. It has been argued that IQ can help find a limiting factor but after that limiting factor (around 120-130 IQ on a 15 SD scale) it stops being as useful for prediction. To explain in a better way, "genius" has stopped being linked to a specific IQ. Instead, it's thought that a minimum IQ of around 130 ~ 120 is needed to be a genius, but there is no set point of IQ where you are automatically a genius. You could have 180 IQ and not be a genius, or you could have 120 IQ and be a genius.

As far as I know (I might be wrong) IQ is especially useful at finding exceptionally low-skilled individuals.

So largely it's controversial in that it represents a universal intelligence, It's less controversial that it's some sort of useful construct which predicts a great deal of life outcomes in western society with decent accuracy within the groups it was designed to test (Western-cultured English speakers in particular)

As I recall, among experts this use of IQ testing is controversial.

That depends a lot on who you call expert. There are people with an ideological agenda against IQ and you may have read books arguing against IQ. That doesn't mean that's the psychometic community doesn't still consider IQ test to be valuable. It doesn't mean that IQ isn't a tool valued by organisation like the EPA.

The usage of the EPA is clearly not standard usage of what the test was desgined to do. If you want to argue that you oppose the usages of the test for purposes besides what the original purpose of the tests you attack the basis on which the EPA decision against mercury pollution rests.