How's the build tooling these days? Last I tried, it used some jbuild/dune + makefiles thing that was really painful to get up and running. Also there were multiple standard libraries and (IIRC) async runtimes that wouldn't play nicely together. The syntax and custom operators was also a thing that I could not stop stubbing my toes on--while I previously thought syntax was a relatively unimportant concern, my experience with OCaml changed my mind. :)

Also, at least at the time, the community was really hostile, but that was true of C++, Ada, and Java communities as well well. But I think those guys have chilled out, so maybe OCaml has too?