You're right, and I ought to have mentioned the difficulty of implementing something like that for Clojure. So maybe the issue is more holistic, which is that it's hard to tell how it's positioned: it's not quite the sort of language that drills as deep as possible into the affordances of being a Lisp, but it's also not quite the sort of language that does everything just well enough, given its investment in, for example, immutable data structures. That doesn't stop me from using it, or presumably anyone else who gets value out of using it, but I sort of idly wonder what the cases are that it's uniquely suited to.

It might not matter: maybe being the obvious right choice for some use case in the abstract isn't that important, and contextual factors re who's doing the work and how they think are just as relevant to choice of language. Still, it seems like we tend to talk about languages now in terms of their most indispensable applications, for better or for worse.