To be clear, I didn't say Rust offered perfect code. But supposedly better code comes from Rust, as you're arguing.

While Rust as a language isn't more complex, the paradigms are different. Games often have trees and lists, which are a real pain in Rust. To do things right in Rust requires learning new ways of doing things - not something game devs want to spend time on. They've been working with the same horse for years, so they keep riding it.