Can’t help but cringe when anyone uses caste to describe someone else’s status, as it perpetuates the validity of that system

The caste that you're born with decides your life quite a lot unfortunately. Due to historical wrongs done against individuals belonging to the "lower castes", they are more likely to be born in poverty, thus making them more likely to have life that can be considered of "low quality". Humans do not have 100% agency in their actions (no matter what stories of "self made" successful individuals would make you believe). Society and culture has a huge influence on the lives of people for the better or for worse. Historical and current wrongs done by the caste system against individuals belonging to the "lower caste" are clearly unjust. This is what I was intending to showcase.

I believe modern India has rejected this idea, even though it’s deeply baked into culture and I’m sure conservatives still believe in it today.

You are contradicting yourself when you say this. Isn't today's Indian culture "modern India"? Aren't the "conservatives" (who have absolute majority in both houses of the Parliament) modern India? Or is your definition of "modern India" that of a utopian India? Cuz lemme tell you mate... India is far for utopian right now.

You didn’t have to call out that these people are the lowest caste, couldn’t you have said they are the poorest or most disadvantaged group or some other adjective?

I absolutely did have to call them "lower caste". You're right. The caste system makes 0 sense. It is a social construct. However, this doesn't mean that its effects aren't real. Caste affects, and has affected millions of innocent lives terribly for a thousand years. Using "another adjective" according to you, shifts the blame from the caste system onto something else. These aren't just "poor people". They're a large chunk of India who've been treated like slaves since a long long time, and are being treated like that today as well, all because of the caste system. I thus have no interest in using euphemisms like "disadvantaged group" or something stupid like that.

It horrifies me how successful the caste system was at segregating groups of people and your usage of that language put you in that category of conservative people who believe in it.

So basically you're telling me to pretend that the caste system doesn't exist. "Brahmin? What is that? Never heard of it! Dalit? Never heard of that word!". As I said before, while segregating people into castes is stupid (and evil), it doesn't mean that the effects of this segregation don't exist. Hence, when you have to point at these effects and explain their origin, you HAVE to invoke caste and all language associated with it. Let's use your language for a second here. These "disadvantaged people" are disadvantaged because of the caste system. They are disadvantaged BECAUSE they belong to the "lower castes". Why should I lie here?