That is a ridiculous assessment of Hinduism and Buddhism.
Was Krishna a Kshatriya.
The vast majority of the Rishis belonged to the lower economic groups. Caste system was solidified later on.
Many Hindu sages and saints have arose from the lower castes like Sree Narayana Guru, Guru Raidas, swami Vivekananda, Dadu, Tukaram, Guru ghaidas, Tiruvalluvar, Gohar,Kabir and others.
VAlmiki and Vyasa, who wrote the RAmayana and mahabharatha were from the shudra castes.
Also one from any caste can become a sannyasin or a propagator of Hinduism , in hindu society.
Many hindus from the lower castes have become sannyasins.
In the arya samaj, anyone from any caste can become a priest, if he has the aptitude and skills for it.
