I do like the underlying ideas, and OCaml has been on my radar for a while. However, from my experience, functional languages with a big F always tend to feel a bit too "academic" when writing them to gain enough mainstream adoption.
Imperative code with functional constructs seems like the most workable approach to me, which rust, go, and other languages like kotlin, crystal etc. all offer.
Ocaml, yes, but not haskell. It does include these things the parent wants, but similar to how Rust ends up being quite "captured" by its memory semantics and the mechanics necessary to make them work, haskell is "captured" by laziness and purity and the mechanics necessary to make those work.
Also, syntax does actually matter, because it's the first thing people see, and many people are immediately turned off by unfamiliarity. Rust's choice to largely "look like" c++/java/go was a good one, for this reason.
I learned SML/NJ and OCaml a bit over 20 years ago and liked them, but when I tried my hand at Haskell my eyes glossed over. I get its power. But I do not like its syntax, it's hard to read. And yes, the obsession with purity.
I actually preferred SML/NJ when I played with writing it, but OCaml "won" in the popularity contest. Some of the things that made OCaml "better" (objects, etc.) haven't aged well, either.
Still with OCaml finally supporting multicore and still getting active interest, I often ponder going back and starting a project in it someday. I really like what I see with MirageOS.
Yep, right there with you. OCaml was only ever better in my view because it had developed enough libraries to be an actual pragmatic choice, unlike the other languages in that family. And yep, Rust is perfectly good too, IMO, but I do find that I rarely-to-never actually care about all the zero-cost abstractions that make it "hard" to use.
OCaml's object system is very nice, though. Structural typing with full inference is pretty awesome, and it also cleanly decouples subtyping from implementation inheritance.
Imperative code with functional constructs seems like the most workable approach to me, which rust, go, and other languages like kotlin, crystal etc. all offer.