Also JVM languages are surging even though none have a specific killer app.
But Clojure is still niche. And is the most powerful/simple of them all. I think there’s something else going on, too much power & simplicity in a language doesn’t yield to mass appeal - why?
the fact you could get roughly the same order of magnitude performance as C in an environment that didn't need tons if #ifdefs to work on various platforms was amazing.
1. Write Once, Run Anywhere
2. GUI in the standard library
3. Way less complex than hyper-complex C++
4. Garbage collection
5. Memory safety
6. Applets that ran in the web browser
7. Comprehensive standard library
8. Free compiler and JVM for all major (at the time) operating systems
Some of these things have ultimately not worked out, but at the time, all of the aforementioned features helped propel Java to huge success.