> I think there's a very obvious distinction between the kind of "3rd party" that is your chosen OS distribution and the kind of 3rd party that is "some person on github or crates.io"
That tells you more about crates.io than consuming prebuilt binaries.
Some Linux distro ship both source code packages and prebuilt binaries. This has not been a problem for the past two decades. Why is it suddenly a problem with Rust's ecosystem?