Let me rephrase my thoughts to better express myself.
I mean if using Clojure, knowing Java and the JVM is a must.
And, unfortunately, using only ClojureScript still requires knowledge of at least the JVM, but eventually Java too. I wish this becomes less true in the future, but today one must install and configure the JVM by themselves, and they must either know how to bootstrap the ClojureScript compiler into a Java process, or use Clojure based build tools like Lein and Boot. Both of which requires Clojure (and thus) Java knowledge to extend. I’d like to see a full ClojureScript ecosystem. Lumo is a great start. A ClojureScript compiler in ClojureScript or at least wrapped in a cli that bundles the JVM, with a build and dependency tool in ClojureScript or similarly bundled.