This is indisputable. Denying IQ and its heritability is equivalent to denying global warming. It’s settled science. Dysgenics is certainly possible. I think technology like iterated embryo selection and genetic engineering will come into common use before dysgenics kicks in. China is already investigating these possibilities, and their culture does not have the same memetic immune response to such ideas. After one country makes it legal, competitive pressures will force the rest of the world to do it, too. Iterated embryo selection could conservatively raise IQ by 60 points, likely much much more: http://www.nickbostrom.com/papers/embryo.pdf
A government would have to be supernaturally incompetent to allow such a gap to develop.