> They can both express the same concepts

Only in the turing tarpit sense. Out of the box, they have very different capabilities. For example:

Higher-kinded types: easy in Haskell, hard in OCaml, mostly impossible in Typescript.

First-class modules: OCaml has them, Typescript can sort of simulate them with extraordinarily unsafe prototype mangling stuff that you should never ever use, impossible in Haskell

Open variants: Easy in OCaml and Typescript, hard in Haskell