Imagine for a second that, controlling for all environmental factors, the average IQ of men was shown to be 3 points lower than women. (Totally hypothetical.) Additionally, women in this world outperform men at chess by a noticeable margin.

There is a valid argument in this case to be made about how the reason women are better than men at chess is partly biological, and that chess diversity programs should be cognizant of this. How would you propose this be brought up in today's climate without offending people?

I don't know if you haven't read the manifesto, or are happy making simplifications for the sake of making conclusive moral statements, but it is wildly dishonest to claim the manifesto argued that "women are genetically inferior." It argued that on average, looking at various traits and preferences, men and women are better at and care about different things, some of which make them better suited -- again, on average-- to some professions than others.

You can disagree and that can be a fun internet argument, but judging by the reaction to this manifesto, the sheer outrage while misrepresenting the manifesto's content, sort of demonstrates the author's meta-point about ideological homogeneity.