I've noticed this as well, but see it mostly as "A players hire other A players, B players hire C players". The top tier of Indian execs/management that I've met will hire diverse teams, just like the top tier of every other ethnicity will as well. There's simply not enough people at the top to put a racial/ethnic/caste filter on it. But then once you get down to the second tier, people will happily hire people like themselves, because at that level you're hiring on vibes rather than data and similar people give you fuzzy comfortable vibes.

Unfortunately most Fortune 500 companies are in the hands of B players now, and it goes all the way up, with the government (multiple governments, really) being in the hands of B/C players. The A players are happily retired and pulling strings in the background with their 501(c)4s.