[misja111]

Given expert skills in both Haskell and Rust, Rust is by far the fastest performing language. And if you use idiomatic Haskell the difference is even bigger. E.g. if you use lots of Monad transformers and lazy evaluation.

[pjmlp]

The optimisation lies between keyboard and chair.

Plus if one lacks the ability to write high performance Haskell code, they definitely aren't experts.