The Rust code is very non-idiomatic, which is probably part of the reason why it seemed difficult to put together and why reading it is a bit of a chore. Compared to Zig or Go, naively translating C code into Rust isn't going to work nearly as well. This isn't necessarily because Rust is more complicated (although it definitely is) but has a lot to do with the fact that it's semantics are inspired almost as much by OCaml and Haskell as they are by C and C++. It's not surprising, then, that someone who is predominately a C programmer would need more than a couple hours to be able to really judge the difference between the languages.