The thing is, Haskell's pretty much the only language with anything approaching a "sufficiently smart compiler". And it performs its optimisations by having a great deal of knowledge it gets from the type system. No, it isn't faster than Rust, but it's an open research problem and I think it's awesome people are still working on it when most platforms have given up.

Besides, it turns out that linear types are useful _without_ performance optimisations: they're very good for modelling state machines e.g. socket lifecycles.