Unfortunately Rust does not even do full source bootstrapped deterministic builds themselves. Their release strategy is entirely the honor system, where everyone trusts their pinky swear that a single computer or person will never be compromised and allow for the injection of malware into the binaries everyone downloads from rustup.
The only reason we have even the crazy long bootstrap path we have today at all is the hard work of mutabah, an individual independent hacker that does it as a hobby.
The rust team seemingly considers memory safety as the only security problem that matters, and supply chain attacks out of scope.