In what ways is Rust more pragmatic than OCaml?
OCaml is great for the application level stuff, and also performs quite well in general. But for building fundamental parts of the stack in which perf is important (like the multi-threading runtime, the garbage collector, etc.) you need to drop down to C++, C, or Rust.
OCaml is definitely much nicer to use than C and C++. But I don't find it that much nicer to use than Rust TBH.
I find OCaml quite a bit nicer to use than Rust, though in a lot of ways that's due to my preference for structuring code using modules and functors.
However, due to Cargo and the fact that Rust has good Windows support, I end up reaching for Rust much more often than I do for OCaml.