Caste system does not define Hinduism, just as polygamy does not define Islam.Hindus is not comparable to Christians, Sikhs. Hinduism is not a religion, it's a 3000 year old slave making cult that somehow made it to 21st century because of Indian continent's cultural backwardness and low IQ.
Hinduism needs a global ban. The hundreds of millions of lower castes must be liberated.
Caste system was a corruption which got added later on, and we are working to remove that from Hinduism.
Though, I agree on your point that Hinduism is not a religion. It is a way of life of this subcontinent. The term 'Hindu' was given by Persians to people of this land living on the opposite side of the river Sindhu (Indus).