The strength of Java for many years has been the platform, and indeed the surrounding ecosystem, not the language. In that sense it's no surprise that there is a lot of effort going in to providing better languages on that platform.

The reason I'm not using Clojure is that it's based on the Java platform. I keep hearing that JVM is nice because there are good libraries, but I haven't figured out what the good libraries are. Sure, there are some nice platform independent abstractions for common operating system interfaces like file and network I/O, but it still lacks lots of stuff.

The problem with Java libraries w.r.t. modern high level languages is that Java libraries are built on Java abstractions. It doesn't matter how high level the new language is, but when interfacing with Java libs, you have to stick to single dispatch object oriented programming. So in the end, there are many cases where you use the Java library through some wrapper layer written in Clojure or your Clojure code ends up looking a lot like Java.

Once you add a wrapper layer shim between your preferred language and the platform, it doesn't matter what's underneath. That's why I like to stick to languages that are built on native code and libraries, C and Posix and Unix API's with some Linux and/or BSD additions. Of course, if you want to run on Windows, all the code has to be duplicated since Win API's are different.