Clojure as a data-oriented language is great in itself, but I can see why someone would choose say R or Python for BI/data science due to the ecosystem. Clojure can of course freeride on the Java or JS ecosystems, but I don't think those ecosystems offer the same breadth as R or Python either.
Try Hy (http://hylang.org) - an excellent Clojure-like Lisp in Python.
There's a difference between "best tool for the job" and "most widely used tool for the job" at this moment in time. People's habits sometimes take years or decades to break (if they ever do).