> we know it was historically very bad

For the people living in those historic eras. We don't know the effects it has on people living in the modern era.

And then you have to make the leap on why tech companies should be enacting social justice in the first place. They're not the guardians of society. Social justice is inflammatory and hiring is basically a zero sum game because "diversity" doesn't affect head count (other than for the liberal arts majors and recruiters who have made careers out of the diversity issue)