I've done a few small projects in OCaml. It's a brilliant language that I deeply enjoy using. But the situation for newcomers and those who don't have established patterns is bad. It's hard to do anything nontrivial from scratch, and the community doesn't seem to have any consensus around dependency management, builds, project structure, and so on. Make and autotools may work for you, but it's not like your setup is on the ocaml.org homepage, reproducible by an application developer in five lines of shell commands.
It's common now in some language ecosystems for the default tooling to just generate all this stuff for you, and you move on to writing code. So if you're e.g. a JavaScript developer who is interested in functional programming, and you're used to npm or whatever, it's a difficult start.
The commenter I'm replying to uses an entirely different toolchain, and the frequently-recommended Cornell book (https://www.cs.cornell.edu/courses/cs3110/2021sp/textbook/) uses ocamlbuild and utop and makes no mention of Dune. If you (understandably) happen to land in the official OCaml manual at https://ocaml.org/manual/index.html instead of the page you linked to (which I can't find from ocaml.org, by the way, but you're right that the ocaml.org tutorials do mention Dune and opam), then you don't see Dune or opam mentioned at all. I get what you're saying, but I don't think you could disagree with the premise that there are parts of the OCaml ecosystem that a newbie would land in and be confused or misled by here.
That's fine, but if you go to https://ocaml.org/ and click the big 'Install OCaml' CTA at the top of the page, it takes you through installing opam, dune, and ocaml-lsp-server. And as per the latest OCaml Survey, it looks like the majority of the community are using opam and dune: https://docs.google.com/forms/d/1OZV7WCprDnouU-rIEuw-1lDTeXr...
Do some of the doc pages need to be updated? Yes. Do some universities take a long time to update their course materials? Yes. Does this mean there's no conensus? No.
There appears to be a rough consensus but it seems to have emerged relatively recently. I learned OCaml about two or three years ago and at the time the best tooling was Tuareg and Merlin in Emacs. Fortunately for me I love Emacs, but I found the Dune documentation poor and overall I got the sense that the OCaml production ecosystem (vs academic) is largely dictated by Jane Street these days, but the community is kind of quiet about the extent to which Core is the "real" standard library and the default stdlib is an academic curiosity. For one thing, the community seemed to be in a transition period between ocamlbuild and Dune, as the official resources recommended ocamlbuild and the community said everyone uses dune.
Yes, this is changing, and these changes have been ongoing since about 2013 when opam was created. But it's true that they're accelerating. I think it's reaching critical mass. so yes a few years ago I would say your points would be valid, but today they are less so.
Dune itself is only few years old. And there has been quite a lot of work on consolidating ocaml.org as a clear entry point for newcomers. But that is still an on-going work.
It's common now in some language ecosystems for the default tooling to just generate all this stuff for you, and you move on to writing code. So if you're e.g. a JavaScript developer who is interested in functional programming, and you're used to npm or whatever, it's a difficult start.