Does it do more than using relative paths in a Cargo.toml would do?
I think this thread is about copying and pasting code versus using a small library in the Go case, which might be a philosphical difference with Rust.
It might help to point out that vendored crates are compiled from source making the required review process referenced by that poster just as possible with server crates.
It's even used for releasing the official Rust tarballs as we now employ crates.io dependencies in the standard library and the compiler.