Take ownership of the pipewire package on Crates.io
It looks like the pipewire name on crates.io (the package registry for Rust) has been name-squatted: https://crates.io/crates/pipewire
The author seems to have a couple of actually-legitimate packages, so I don't think it's malicious per se, but they're also not doing anything with this package namespace. The only code in the repository (or the uploaded package) is the generic "hello world" type template that is generated by cargo when you start a new project, which was committed 7 months ago.
Even if the pipewire developers (yourselves) have no interest in developing pipewire bindings for the Rust language, it would probably be better if the project held ownership of the namespace for future potential use. The current holder would probably be open to that if you reached out.
The (empty) repository is here, and their email is available on the crates.io page linked above.