I'm sure it happens at small companies, but at large companies I've never seen it. It wouldn't be allowed to stay that way if it did happen. The number of times I've seen it happen with Chinese and Indians teams, relative to how rare it is for white-only teams to exist, seems highly improbable. White people are the plurality if not majority at most big American tech companies, so if it's all just statistical noise it should happen more with white people and that just isn't what happens.
I have seen enough white-only teams while at FAANG. Those were not in SV but in smaller US cities. Of course that was rare but then again, chinese-only or indian-only teams were rare as well.
