It is rewritten to a different language and many people find Rust easier to read, it has better type hint support for IDE etc. Also, you do not lose all the safety, there are still many rules enforced, such as safe linking, no undefined functions. Unsafe Rust means that all parts of code which do illegal pointer magic are explicitly marked with an "unsafe" keyword. You can now go one by one and fix them.

Once the codebase is all Rust you can start introducing Rust idioms and patterns. Basically step 1 is to get it working in Rust then step 2 is to clean up the Rust to actually take advantage of the language.

From the article: "The next goal is to convert the codebase to safe Rust."

In addition to other points about making it progressively safe, unsafe Rust is still safer than C. https://bsky.app/profile/ssg.dev/post/3lkjogvm2c222