I haven't seen a racial aspect where whites only hire whites either. I have worked in places that only hired white/black/asian and in others that only hired white/black/indian. I have never seen a true mix of asian and indian aside from government work. I've always wondered about that.
It feels like white/black/brown/yellow is not as acceptable yet. But various combos are.
A lot of it is nationalist or language based. A black person from the US is treated as the same as a white person from the US vs a white person for Europe generally because of language differences.
I've collected some of the more egregious things I've heard around women and minorities in tech.
At a well-known company, while it was small, regarding hiring an office manager, the female head of HR said "I don't want to say it, but I'm leaning towards [the female candidate over the black candidate] because she's a woman." She was hired and fired 3 months later.
At a company you haven't heard of, "basically, the next person we hire has to be woman."
I've seen recruiters search for common (white?) female names in LinkedIn for reachouts. Someone's going to subpoena LinkedIn searches and there's going to be an ugly class action suit against companies doing this.
"Now that we hired <male name>, we really need to ramp up hiring women."
A very competent women in a good role with a stay-at-home husband told me she has it easy because tech companies are bending over backwards to hire women.
At another well-known company, reviewing resumes, someone said "this resume would be a 'no' for a male."
I've also see a lot less focus on diverse racial hiring, and interestingly, at a number of companies, there are teams of 10 people who are either all Chinese or Indian. I've worked in one in my career, and it wasn't good. I obviously didn't belong.
Some of those women have expressed annoyance at this because they feel that they are being touted as poster-children for the managers. The women also express concern at how they are potentially being pushed into roles that they aren't necessarily qualified for and are unintentionally being set up to fail due to not having the necessary experience to fill a position.
It's important to remember that the women are absolutely not at fault for their managers' actions. Whenever this topic comes up in conversation, I always encourage them to learn as much as possible and jump on top of opportunities that come their way.
That said, I am lucky enough to be able to work with some incredibly respectable and talented women, some of who have skills FAR outshining mine.
This is incredibly common but HR and the usual diversity folk don't seem to touch on this topic much. Not being part of the in-group may result in a less-than-stellar performance review regardless of work output. Some of them purposely accumulate sacrificial lambs so they have more positive reviews to give out during stack ranking, and they need scapegoats to take the fall when the time for forced attrition comes.
Just to point out that retributive social justice is a major factor in the ideologies which brought about Nazi Germany, Stalinist Russia, Maoist China, Pol Pot's Cambodia, Castro's Cuba, and so on. Millions of people died because of "justified" retaliatory ideologies. That's not a mistake that needs to be made again.
I am personally attempting to make sure that equality of opportunity, rather than retribution, is the motivating factor. The earlier down the slope we cement that, the better.