I think we sort of ignore this as an industry because we still look at DE&I primarily through the lense of representation and proportions and not in terms of actual power being wielded for the benefit of an in-group at the expense of the out-group. You don't need to be an outright majority to wield political power like that. And it can easily go against industry wide trends in the context of a specific company too if cliques like this form.
It's also because it's not exactly racial discrimination. They didn't hire almost all Indians because they thought white/black/hispanic people were inferior. At least I don't think they did. It was more network based and as immigrants their network were mostly other immigrants.
Plus there's a lot of discrimination going the other way where American born developers got the preference. Again, not really due to racism (at least AFAICT) but more because of culture & language barriers.