“Please build the perfect system. Because I specified ‘perfect’ any flaws are due to your incomplete implementation, not my awful brief.”
If the person writing the rust spec was a client I would have to drop them because they would be setting themselves up for dissatisfaction.
You can't do that with Rust because "Rust's type system" is literally just the vague concept of "a type system that is safe". The implementation of this ideal in rustc can have flaws, but Rust itself cannot, because Rust itself has no flaws by definition.
You seem to be implying that because of this, Rust has no definition of its type system (other than whatever happens to be implemented in the current compiler). I would disagree.
As evidence, I would like to point out that not a single person argued that this flaw was not a bug, but was in fact the officially defined behavior. Clearly, the community has a shared understanding of what Rust's type system "ought" to do.
This is a nice ideal, but it doesn't actually exist in concrete terms as a design. It can never have flaws because the definition of it is just "rustc without all the flaws".
Sweet. But why should anyone care..