https://www.quora.com/What-did-Buddh...e-caste-system



this is the same guy who claimed that even though in non materiel world everyone is equal in the materialistic world(earth), Brahmins and Kshatriyas are indeed superior to others. and every buddha after him (bodhistatwas) will only take birth in either purebred Brahmin or Kshatriya Family.

as he was born in Gautama Sakya clan of kshatriyas, next buddha will come from a pure Brahmin family.