Is there a good reason to say that Rust is an OCaml dialect?
It's not a bad thing, but Rust has very little in common with Haskell/Ocaml; aside from stealing a couple of good ideas.
No typeclasses (and associated goodness), GADTs, HKTs, Monadic IO, first class functions, generic deriving, higher rank types, existential type, etc. These are bread-and-butter features in day-to-day Haskell work. Rust's type system isn't powerful enough to build the vast majority of the tools that Haskell programmers use every day.
I don't mean this as a criticism; The Rust design seems solid. But different priorities lead to different trade-offs, and the end result is a very different type system.
Also, traits objects are existential types, and closures & functions are as first class as they are in Haskell (main difference is a bit more verbosity).
There is, maybe, grounds to say that all languages with S-expressions, first class functions and garbage collection are just a type of lisp.
But I would not say that all languages with strong static typing, some form of type inference, algebraic data types, patterns matching and functional programming features, are a dialect or OCaml, or ML.
Haskell has these too, but it has more stuff like more emphasis on immutability and purity unlike Rust and OCaml.
Also, the first Rust compiler was written in OCaml.