If Go designers weren't so much anti-modern language design, in many scenarios where people are rushing to do RIIR, they would be better served with Go, if those modern features were part of the language.
Having said that, there are still OCaml (as you noted), Haskell, .NET languages with Native AOT, JVM languages with GraalVM/OpenJ9, D, Nim, Swift, ....
And if one wants to get fancy with type systems, Idris, Dafny, FStar,..
I think OPs general point, although maybe not what they stated is correct: it’s easy to write GC’d code. It’s “easy” to write code with manual memory management. It’s “easy” to write RC code. But it’s hard to write borrow checker code. And that will probably limit adoption, even though the goals of Rust are good.
> If GC is an option and you want all the nice parts of Rust, use OCaml
So are you saying it would be possible to use a hypothetical "non-GC-enabled" OCaml compiler that complains if GC'd code is invoked/generated, and it would be a similar experience as using Rust?
No, simply because GC isn't an optional part of ocaml's design. You can "disable" it only in the sense that you stop any frees from happening.
In order to do away with Garbage collection you'd need to completely change the type system, and while you might get a result which ends up looking a lot like ocaml, it won't be ocaml any more than ocaml is sml.
This is what Rust started out as, by the way. In my opinion, it should have stayed that way. Post-Mozilla Rust has been nothing but a gigantic disappointment.
Early versions of Rust "started out" with GC: the language was broadly similar to Golang, though with a lot of influence from Ocaml and functional languages more broadly. The comprehensive use of borrowck to avoid GC altogether was only implemented around 2014 or so, hence shortly before the Rust "1.0" release in 2015.
Having said that, there are still OCaml (as you noted), Haskell, .NET languages with Native AOT, JVM languages with GraalVM/OpenJ9, D, Nim, Swift, ....
And if one wants to get fancy with type systems, Idris, Dafny, FStar,..