That's not exclusive to Christianity. Universal equality is a basic tenet of Hinduism (including non violence towards all living things not just humans). I will not get into a debate of what is "Hinduism". I also don't disagree that some people do face a lot of discrimination. Sadly, the old generation needs to die off for this stuff to be behind us.
They may not be having caste-based discrimination but they do have other forms of discrimination. That's why you have terms like heathens, heretics and kafirs.
While I agree that Hindus have more of this caste-based discrimination, a simple search shows that it's not exactly uncommon in other religions in India.
https://scroll.in/article/876000/is-the-caste-system-deep-ro...
https://theprint.in/opinion/indias-muslim-community-under-a-...
https://www.newindianexpress.com/states/kerala/2019/sep/01/c...
I'll reiterate, it's very rare in other religions and uncommon. Mostly remnants of Hinduism. But ask an average muslim or a christian his caste and he will say that he doesn't have one.
Aren't there Shia/Sunni divisions and even centuries long wars?
Not exactly castes, but probably worse.
https://www.newstatesman.com/world/middle-east/2017/08/sunni...
Also see:
https://en.wikipedia.org/wiki/Caste_system_among_South_Asian...
> But ask an average muslim or a christian his caste and he will say that he doesn't have one.
Almost 80% population of India is Hindu. It's obvious that relatively less number of muslims and even less number of christians are gonna talk about caste.
If caste is beyond religion in India, then why did Ambedkar leave Hinduism and urge all of his followers to do so.
Can you tell me one other religion which has the concept of caste in religious scriptures?