My feeling was that a lot of Clojure folks moved on as the data processing stuff moved on from Java/JVM.
My impression has been that JVM-based languages have effectively been on a steady general decline for a while now. Java has fixed a lot of its issues; Kotlin gave the Java expats somewhere to go. And Javascript/Node along with Go drained out the general masses who didn't really want to be on the JVM anyhow.
However, it is interesting that Clojure has effectively disappeared in those rankings.