First of all, I apologize for asking a question that does not directly concern OCaml, but I do not know where to ask this question. I am currently looking for a good build system for C++ as part of my professional activity. I quickly dismissed Autoconf because its portability under Windows has a bad reputation and many projects migrate to CMake or Meson. I just learned that the OCaml project is about to migrate to this tool and I wonder if I have missed something. Do you know the motivations of this choice?
Dune is built only for OCaml projects, it has a great deal of knowledge of OCaml and the OCaml ecosystem built in to it. It isn’t suitable for C++.
I note, though, that you’re confusing several issues. For example, autoconf is not a build system, it’s a configuration system to allow portability of code in multiple operating systems and the like.
I would suggest that if you want to find recommendations for good C++ build systems, you try Stack Overflow. For myself, I simply use Make for building C++ things, but I seem to be old fashioned in this regard.
You can look up whatever C++ open-source project you like better and check which build system is in use. Like, for example, last time I checked Chromium project, it’s CMake + Ninja.