The wikipedia link you provided makes it clear that micronutrient deficiency is a serious problem in the developing world but I could not see any factual support in that link for the claim that micronutrients in general have an interesting dose/response curve, or that micronutrient deficiency in the developed world is any kind of problem for the majority of people. You might want to edit that link to reflect the fact that it does not support the claim "actually being true".
There is some expert support for your view but there is also excellent reason for caution with regard to any claims you might hear about micronutrient supplementation. This is a very popular area with scammers, cranks and the deluded.
I'd be interested in seeing any properly blinded and controlled studies that show that micronutrient intake over the daily requirements has meaningful benefits - if I can gain a few IQ points by eating more fruit and vegies I'll take that deal.
I have experienced cognitive gains that would almost certainly show up on IQ tests by eating better animal sources of micronutrients. Studies would be great.