Debian's repackaging is not useful for Rust developers. It's a tiny tiny fraction of Rust packages (Rust has over 60,000 now), and it's not integrated with Rust tooling. It's not useful for anything other than the few binaries written in Rust that Debian ships.

Debian's policies are simply incompatible with the Chrome-like "evergreen" release model that Rust uses. I feel sorry for anyone who tries to use Debian's Rust. It is an awful experience.