I hope Rust comes of age in a few years. Java, Go, and C# are above 50% "native" speed in every benchmark I've run across, but the mantra continues to be "why would I pick something slower?".

Rust is the answer everyone wants, even if they don't really need it.

An aside, C# in .NET core is getting very close to native speed. It's passed Java in many benchmarks, mostly due to type reification and lack of boxed primitives.

Java is trying to catch up, with active research projects for copying C#'s native types, a "Java on Java JIT" (Graal). And most interesting to me, fiber based green threads.

If these projects bear fruit, we may be only a few years away from Java exceeding native code speed in most applications