There's still hope!

There are a number of much anticipated features that haven't made it into this release. In particular, the multicore GC, which at one point had been expected to land in 4.03, has been pushed back, likely to 4.04.

and when exactly 4.04 will pop up ?

~~ Well, I know, it's hard. ..

I'm guessing after 4.03 and before 4.05?

I really wanted to use OCaml, but it is adding features way later than I can continue to wait. I've started learning Ponylang as my CSP language over Elixir ever since I checked it out several months ago. Maybe OCaml will fit the bill one day. Jane Street's inertia seems to keep it going outside of the academic world, but that's a single linchpin in the commercial world outside of its academic pen.

Many commercial companies (and startups) use OCaml, eg Facebook, Bloomberg, etc

https://ocaml.org/learn/companies.html

I am aware companies, big companies, use OCaml. My point, perhaps not made clear, is that Jane Street is building useful libs, and contributing back to OCaml with 'batteries included' type libraries. Facebook creating a VM and programming language compatible with PHP may be useful to some, but is not addressing the more fundamental needs or issues like bringing multicore to OCaml.

I think that does a disservice to the much greater number of people who are not at Jane Street but contributing useful code and libraries. You also seem to imply that Jane Street is the one 'bringing multicore to OCaml' but that's not the case.

Jane Street certainly contributes a huge amount to the ecosystem, both in terms of code and other support, but they're not the only people pouring effort into it.