It also hasn't changed much in 15 years. Now that could be (and probably is) a deliberate decision. But there are more than enough cases of projects that haven't changed because they can't...they've painted themselves into a corner, and every time they try to change something, something else breaks.

I've felt this way with Python and Ruby and Node projects (it is a major complaint in the RoR community), but have never felt that way with Scala, Java, C#, F#, Rust, or OCaml. Most of the time, when I need to make a change, I just change it, iteratively eliminate any type errors, and once the type errors are gone, the tests magically pass too.