The claim that right wing science denial has had no real impact is absurd. Just take the efforts of Republicans in regards to anything related to climate change. Or how rejection of the science behind transgenderism has influenced their stance on LGBT rights.
What really surprised me was when he talked about IQ research and human evolution. I'm pretty sure that scientists have found no connection between biology and intelligence, and the author more or less asserts that there is a connection that "the left" has been trying to conceal by cutting funding towards that area of research.
Then there is the race stuff and evolution. The author accuses leftists social scientists of denying the science behind race, ignoring the actual research done by biologists in this area. Current research shows that human genetic diversity is more of a continuous gradient of allele frequencies. In other words, grouping people into discrete populations based on genetic similarity (i.e. races) is totally arbitrary. Having 10 races would be no more valid than having just one race or a billion races. Pretty ironic that he's espousing pseudoscience in a piece meant to call out pseudoscience.