Footnote 1 makes no sense, suggesting that the only way to get access to "a bunch of other useful code" is to embed it into a C program and that understanding your dependencies is somehow easier in Javascript.
In reality, Quicklisp[1] offers effortless access to over 1200 libraries and programs. It's nowhere near the 200 thousand packages in npm, but the overall quality is good and these libraries cover a surprisingly large number of things.
The post tries to display Clojure as "Lisp, but with access to open source". Clojure is a fine programming language, but it's also completely different from Common Lisp. CL has high quality optimizing compilers performing extensive type checking, a powerful object system, easy access to C libraries, etc. If you need Java interop, you can just use ABCL[2].
[1]: https://www.quicklisp.org/ [2]: http://abcl.org/