I think OCaml is more of symptom of the people who they hire. Most companies don't want to hire OCaml and Haskellers. They fear they would be too expensive, and requires clear thinking so you can't hire bottom of the bucket devs.
If you want to hire the best and willing to pay that is no longer a concern
I interviewed with them, a long long long time ago.
They use OCaml because it is explainable. Which it is. They use it like a non-lazy version of Haskell -- side effects are used rarely if ever. So there's no nonlocal behavior in the code, which makes it easy to reason about. And that kinda matters when a lot of money is at stake.
Incidentally, Standard Chartered has their own compiler for Haskell, without the laziness. The group is led by the guy famous for Cayenne (the first dependently typed Haskell dialect).
> Most companies don't want to hire OCaml and Haskellers
Most companies don't even know that these are programming languages. Also don't assume people interested in these languages are "the best". Regarding JS, this is all hearsay, but I think nowadays they hire good profiles (competitive programmers / olympiad winner / top graduates from prestigious schools), ask them hard leetcode questions, and teach them OCaml (which anybody can learn, not particularly hard. Their talent pool isn't restricted to the OCaml community, as it used to be when they were less famous, except for niche use case (compiler work and so on...)
I'm not saying people interested in OCaml are the best. I'm saying you don't have to worry about smart people being incapable of understanding OCaml.
You got the direction the wrong way around.
Ask to introduce OCaml at any company. The first thing is they're worried about is not being able to find people. To which the answer is to train them. But then they're worried some people just won't be able to learn ocaml quickly enough. To which my answer is hire people who are good enough to learn it quickly. But then they get worried those people are expensive. Ultimately it comes down to not being willing to pay.
Companies that want to maintain the ability to outsource or hire cheap developers if push comes to shove is actually pretty common. They want commodity labour.
To be fair, another reason for avoiding OCaml, or other kinds of almost-esoteric tooling is a business need for longevity of support and of the ecosystem: if you choose something like Java you have a reasonable belief that, at any point in the next 20 years, if something breaks then you’ll be able to call a phone-number and pay through the nose to get it working again. Companies don’t mind paying large amounts of money for an expert, provided those experts are available. But in 2024 try finding an expert for some dBase 4GL system from 1998 that only runs on AS400.
OCaml has been going since 1996 and is managed by an academic institution in France. It's also much more portable and malleable than dBase for DOS on old iron.
I interviewed there and can confirm they don't require you to know any OCaml (though I did have some Haskell on my CV - I don't know if that was a factor in hearing back or not). The questions are LC-adjacent but the interview is structured such that each question builds on the previous one.
If you want to hire the best and willing to pay that is no longer a concern