Is the caste system inherent to Hinduism? Please read the body of the post
Sometimes some really vile things aren't parts of a religion but parts of the culture of the place where those vile things prevailed. So in that case if someone who's vehemently against those vile things they don't have to leave the religion, they can simply keep practising the religion while taking a stand against those vile things. But if those vile things were inherent to that religion, they have to leave the religion if they are vehemently against those things.
If the caste system is a inherent part of Hinduism and one is vehemently against the caste system then they have to leave Hinduism. If the caste sysyem isn't inherent part of Hinduism and is just a cultural evil then they don't have to leave Hinduism.
So my question is: Is the caste system inherent to Hinduism? And if someone wants to permanently remove the caste system from existence can they do so without going against the religion (Hinduism) itself?