Adding a GC to Rust might honestly be easier than getting the OCaml ecosystem to adopt something that works as well as cargo. It's tragic, but that's the world we live in.
Of all the things I'd change about OCaml, dune is very much down the list. It's flat out better than cargo in that it's an actual build system with build rules driven by file dependencies, not simply a glorified frontend for a compiler. Not great, but better.
Now, upstreaming OxCaml's unboxed types and stack allocations? That might actually take longer than adding a GC to Rust.
Now, upstreaming OxCaml's unboxed types and stack allocations? That might actually take longer than adding a GC to Rust.