If Rust didn't have good runtime performance, it wouldn't be worth looking at over SML, Ocaml, or Haskell.
> So let's get back to the performance of the code generated by the Rust compiler, shall we?
"Shall we" just stick our heads in the sand too? No, you don't fix problems by ignoring them or pretending they aren't a problem. Slow compilation speed is a problem if you care about developer productivity and quality of life.