I agree that in general most want to integrate new languages with their existing code bases (rust-bindgen automatically generates C bindings, ABI tests, etc. us

I agree that in general most want to integrate new languages with their existing code bases (rust-bindgen automatically generates C bindings, ABI tests, etc. using libclang to access C and C++ from Rust, and for each language there are tools to generate bindings and ABI tests for Rust code, e.g., the cpp crate generates C++ wrappers around Rust libraries). The consultancy company developing c2rust specifically helps clients translate their apps to Rust. IIUC these clients want to move from C to a memory and thread safe language without loosing performance. c2rust is the first step in that process. It mechanically translates C into "C-looking unsafe Rust". The engineers then go and start migrating from unsafe Rust to safe Rust incrementally. This is a long process, c2rust speeds up a small fraction of it, but most of the engineers time is spent into translating unsafe Rust into safe Rust, and then refactoring safe Rust into idiomatic Rust.