> Rust has never advertised itself as a panacea.
Rust may not, but random Rust programmers rave about it all the time as if it were a panacea.
> expand on what is expressible within the safe subset
I hope that Rust itself keeps going further in this direction. Even with the residual unsafe code, bounds could be implemented to limit the possible damage, and correct it as soon as feasible.
Rust has never advertised itself as a panacea.
I agree that Rust is not the best language that can theoretically ever exist. I do disagree that it is possible to have a 100% compiler checked memory safe language. There will always exist some portion of these systems that need to be verified by hand. And that's okay. The goal here, and how other languages could improve upon what Rust does, is to do what Rust did to other languages: expand on what is expressible within the safe subset.