> but that's functionally impossible: nobody is rewriting their application twice to see what rewrite is better.

Agreed, and hypothetically the 2nd rewrite should still be better than the first. So the language would have to make it significantly worse to outweigh the yet again experience in improving things.

To be clear though i'm not stating that every rewrite is assured to be better. However a carefully considered rewrite has a much easier time making decisions learned from any warts discovered in previous implementations. God knows there's always some warts.

As a Rust fanatic, i wouldn't expect Rust itself to be due to the performance gains. It's not expected to be faster than C/C++ typically. Just comparable.