Thank you for the great feedback! The goal was just to show the ClojureScript version of the original demo (the first version of it). So there is no collision detection, sound, etc. I think ClojureScript has too many things to provide in this field.
It's definitely an interesting demo and certainly not the first time a less obvious (i.e., imperative) language has been used in game dev: just today on a separate discussion people were talking about use of GOAL (a compiled dialect of LISP) in PS1 game development. Pretty cool stuff.