I'm very glad somebody brought this issue up, in a carefully written essay. It is a real problem. I come to Clojure from a Common Lisp background and the issue

I'm very glad somebody brought this issue up, in a carefully written essay. It is a real problem. I come to Clojure from a Common Lisp background and the issue there was exactly the same (in spite of how old the language is): developers had their systems carefully tuned and weren't interested in newbie experience, while setting up a new environment was a major barrier. The good thing about Clojure is that there are people who care about these things — see for example the leiningen and clj projects on github. Leiningen is already way beyond anything that was available for Common Lisp, for example. There's hope.