Rust is very different from Ocaml. Rust is a low level language with a borrow checkers, traits, no first class module system, no GADT, no effects.

The similarities are fairly superficial actually. It’s just that Rust is less behind the PL forefront that people are used to and has old features which look impressive when you discover them like variants.

There is little overlap between what you would sanely use Rust for and what you would use Ocaml for. It’s just that weirdly people use Rust for things it’s not really suited for.