OCaml like a lot of niche functional programming languages has a lot of weight on HN. Or used to for many many years, mostly before LLMs. Jane street is single-handedly keeping OCaml alive and in use in real applications and as such they get a lot of credence.
Whether you agree with what they do or not, they have had a sort of mystique about them (tons of money, quant vests, _and_ a niche functional programming language as a daily driver??? Sign me up!) that HN likes.