The biggest problem I have with Ocaml is not the language, but the tooling and the libraries. The library ecosystem is not even remotely comparable to go or even rust. Jane street core is mentioned as a good option, but that library is the most popular undocumented library I have ever seen. There is not even some normal default structure every library follows (e.g go io.Reader).
Compare this to languages with supposedly "worse" type systems like Java, which has a library for everything and high quality well documented libraries like guava and apache commons. I find it fine to use ocaml for a random weekend whim project, but wouldn't touch it with a 10 feet pole for professional work.