The claim you're debating - "does caste-based discrimination exist" is more likely to be true with an anecdote "I've seen it" than with an anecdote "I haven't encountered it."
Those two anecdotes can both truthfully coexist, but the first one proves the statement while the second doesn't disprove it. The evidence needed to disprove such a statement is pretty large; an individual's work history is not enough to say confidently that discrimination isn't happening.
How many companies have you worked at, 6? How many companies are there with significant indian representation? At Google alone there are far more than six TEAMS with majority indian representation. How could you claim that your experience invalidates someone else's?
Meanwhile, if there are a handful of anecdotes that folks have experienced or witnessed caste-based discrimination, we should be pretty confident that it's a problem.