Eg. Fe-/male and racial differences. They exist, yet they cannot be admitted to and any reference to them will have the political left call you a nazi, racist, sexist and pedo to boot, because the other terms are already less impactful from overuse
Perhaps because, to many people, it seems wrong to set policy based on marginal differences in the aggregate when the policy will affect individuals, and also because people doubt the motives of those who are highly invested in proving a scientific basis for negative stereotypes.
You out yourself pretty badly in implying that individuals can be ignored in gender and race in the name of aggregate statistics.
There is similarity, there is not sameness, and like I said… the people who are fascinated with proving statistical differences in gender and race usually have ulterior motives. Just like climate deniers.
I think this boils down to the fact it's typically just a thin veil for motivated reasoning.
Leftists see racism and sexism everywhere - their ideology focusses on that and they pick up on any excuse they can to label people as that. It's actually a horrible way to treat their fellow humans.
Saying "Asians" are intellectually superior to "whites" is a thinly veiled way to say "and whites are superior to all other non-Asian/white races."
And the claim that "Asians" are intellectually superior to "whites" isn't even correct "because of race." I'm not aware of any real study that attributed racial identity to measure intelligence. Cultural differences? Socioeconomic differences? Country of origin? Sure. Race? Used as a proxy for the former.
This is a pretty weird take. I'm a liberal with a lot of liberal, progressive, and even socialist friends, and basically nobody has a problem with recognizing the statistical differences between men and women.
There's plenty of discussion about how much of those differences are innate biology vs environment, though. And there's discussion about how much overlap there is between men and women - often, there's a lot of overlap, which makes stereotypes not so useful. But the existence of differences? Oh, sure, yes, of course there are differences.
So I'm not sure if you're suggesting something you're not saying ("racial differences in intelligence are innate, not environmental"), or if one of us is out of touch with what 'leftists' think.
ETA: I say "one of us" because ofc I may also be wrong! Most of my friends are well-educated, and both that and selection bias may skew my experiences away from normal