Those languages each target one of those platforms only, i.e. Crystal and Rust for a statically compiled binary, Apache Groovy for the JVM, and Elixir for the E

Those languages each target one of those platforms only, i.e. Crystal and Rust for a statically compiled binary, Apache Groovy for the JVM, and Elixir for the Erlang runtime. Why not use a language that targets many platforms? E.g. Kotlin targets the JVM, Android, and Javascript, as well as is natively compiled. Now that's the real future. Better than using, say Groovy, to target the JVM, then rewriting it all when you want it to run on Android.