In my case i'm comparing it with languages that are also powerful, safe, fast and more well designed for this kind of scenario, which JavaScript or Python aren't.
But if i had just two picks, between JavaScript or Rust, of course i would choose Rust without blinking. But once there is more options.. (in this case you can read my comments above).
And i agree with you, that if you sum it all, maybe you get more productive (as in ready to ship) in Rust than with JavaScript.
C# - requires an obscure runtime (Mono) on most platforms
Kotlin - suffers from JVM's infamous GC pauses and startup time
Swift - not open source (not SwiftUI, the good part)
TypeScript - mostly same problems as JavaScript
Java - same problems as Kotlin
No one has managed to do open source cross-platform development well yet IMO. I'd be happy to be proven wrong.
F#: https://safe-stack.github.io
To watch:
Kotlin NATIVE
Scala NATIVE
Note that even with Scala's complexity, the language's focus is first and foremost domain modelling & expressiveness.
Rust is first and foremost, a language for memory safety and raw performance, it just happens to have some level of expressiveness. Nothing wrong with that either.
Rust will make a great UI language once the ecosystem has matured and async has gotten polished more. If upgrading the "Webpack" of the future meant just resolving compiler errors, we would be in a much better world. Same goes for upgrading dependencies on the frontend, which at my company becomes a blocker every 2 weeks or so due to the NPM security advisories being released, accompanied by the total lack of visibility into the dependencies' interplay that the Node ecosystem gives you.