One comment -- in India, there is theoretically the concept of the "creamy layer", sufficiently rich individuals cannot benefit from reservations, though in practice I don't know how well that is implemented.

Another thing is that casteism is _not_ limited to Hinduism in India. Not by any stretch of the imagination.

Look at the matrimonial sections of Indian newspapers -- there are Christians who explicitly look for a Nadar (a caste from Tamil Nadu which has become prosperous in the past century), a Christian Saraswat Brahmin (a caste from Western India including Goa, where the Portuguese only allowed native Christians of Brahmin origin to be Roman Catholic priests).

Sikhs have castes mirroring Hindu castes, even though their religion is explicitly against the caste system.

Indian Muslims have a different caste system, with people claiming an Arab, Persian and Turkish ancestor (and sometimes people of high-caste Hindu origin), at the top, and people of Dalit origin at the bottom.