as per my understanding, caste system was a exploitative system created by brahmins. they corrupted the people's mind posing as a middlemen between god. at that time if u have to interact with god then u hv to go through brahmins.
All folk god and gods in hinduism were kshatriyas(who really tried to reform Hinduism, breaking all caste barriers) e.g. lord rama, krishna, gautam buddha.
and in medieval times it was devout farmer class like jats etc, who tried to reform people.
And for caste-ism swami vivekanand during Chicago speeches made it clear that there are 2 kinds of hinduism.
1 Ceremonial - its for those who are part of society. casteism exists, still in rural india reforms are needed.
silver lining is
2. Spiritual Hinduism - any caste person can become a sage. Even a brahmin will welcome him without asking his caste. caste is non existent there.
Those banning bhagvad gita are rejecting all 18 forms of Yogas, but still god bless them.