Regarding the reliance on Emacs, might not be the case anymore. When I was new to Clojure, I immediately used an IntelliJ plugin called Cursive. It was/is great, same experience as writing Java in IntelliJ. (https://cursive-ide.com/)
^1 As an aside this is why I'll never be satisfied with plain Java/JavaScript no matter how many new static features they get so long as they remain fundamentally opposed to the build-up style of programming.
^2 By beginner I mean to Clojure; I don't think Clojure is a good language for programming beginners. It is suitable for people as a second or later language, but not their first. So basically I agree the need to explain the preferred editing environment is a hurdle -- if the person's first language was Scheme, maybe there wouldn't be a problem since you don't really-really need paredit or syntax highlighting or auto-indent or anything besides the ability to edit and save text.
^3 For me that's just a separate terminal in a screen session that a vim plugin talks with, though there are others (and probably better, I haven't tried them seriously) for vim.
Coupled with the setting "Settings→Editor→Smart Keys→Surround selection on typing quote or brace." it's amazing.