This doesn't seem like a useful comparison, analysis or conclusion. Clojure is philosophically a Lisp, but as others have pointed out, it isn't usefully the same language as any other Lisp that preceded it or exists today. If this particular example is useful to people who might otherwise think they could reuse existing Lisp code, then I suppose it's saved some effort, but that just seems like a straw man.

Either way, if you get the terminal condition of a recursive function wrong, you will blow the stack. It's true Clojure isn't built to do TCO, but that's a non-sequitur. The idea that you don't typically use recursion in Clojure is ridiculous - for is a macro, it's syntactic sugar over Clojure's recursion primitives, loop and recur. Even if you didn't want to use that, change the nil? check to empty? and it works. I'm not going to claim that Clojure's list/sequence semantics are necessarily the cleanest (the empty _sequence_ in Clojure is nil, an empty list/vector/set etc is not), but they're not hard to learn if you make any effort at all. Again, your existing Lisp experience may or may not help you understand Clojure's data structures, but I am surprised that this is a surprise to anybody.