I think there might be a few misconceptions in your comment, but it's hard to say for sure. This article isn't written in a style that I particularly enjoy, but it's not too long and contains some useful facts that might help dispel those misconceptions: http://utf8everywhere.org

I do have my unrelated niche complaints about Rust's string story (and I have vague plans to resolve them), but Rust's string implementation is my favorite among any other language I've used.