Yes, Julia is an interesting outlier in the design space. My understanding is that Julia gets the speed it has largely by JITting a lot of code for every instantation of a generic/dynamic function that it sees with all of the concrete incoming types.

That's an interesting point in the design space where you get the flexibility of dynamic types (and multiple dispatch!) and good runtime speed. But you pay for it with slower startup times, less predictable performance, and much higher memory usage. You are also married to a JIT. Julia really is designed to be run interactively in a REPL from source. The language isn't well-suited to compiling a standalone executable ahead of time. That makes perfect sense for its use cases, but would make it a challenge to adopt in other use cases.

(For example, I work on Dart which is mostly used for building mobile apps. That means we care deeply about executable size, startup speed, and the ability to compile ahead-of-time to native executables.)