I don't buy this claim. I've written many services with Rust and I'm not slower with it that I am with GC'd languages I also need in my work, such as Clojure, S

I don't buy this claim. I've written many services with Rust and I'm not slower with it that I am with GC'd languages I also need in my work, such as Clojure, Scala or Python. Please explain me where is this idea of slow development time coming from? Is it only because people try Rust for two weeks, cannot get the lifetimes and decide the development speed is slow?