I mean, you can have a tree of vectors also, so I don't see why lists are needed for homoiconicity.
In addition to REPL and macros, I think two other Lispy features are essential:
nil is not just the sad path poison value that makes everything explode: lisp is written so that optionals compose well.
Speaking of composing, Lisps tend to be amazing with regard to composability. This is another line that cuts between CL, Scheme and Clojure on one side, with Python and Javascript firmly on the other side in my experience.
Lisps are as dynamic a languages ever go, unapologetically.
Beware though, that there are today more than one flavor of Clojurescript, nbb for instance still acts just like JS in this regard.
The last time I did ClojureScript in serious capacity was for a school project in 2021, specifically because I wanted to play with re-frame and the people who designed the project made the mistake of saying I could use "whatever language I want".
It makes sense, but I guess I didn't realize that ClojureScript generates some nice runtime wrappers to ensure correctness (or to at least minimize incorrectness).
I guess that means that if you need to do any kind of CPU-intensive stuff, ClojureScript will be a bit slower than TypeScript or JavaScript, right? In your example, you're adding an extra "if" statement to do the type check. Not that it's a good idea to use JS or TypeScript for anything CPU-heavy anyway...
In rare cases, sure, it can add some overhead, and might not be suitable I dunno for game engines, etc., but in most use-cases it's absolutely negligible and brings enormous advantages otherwise.
Besides, there are some types of applications that simply really difficult to build with more "traditional" approach, watch this talk, I promise, it's some jaw-dropping stuff:
SpreadSheesh! talk by Dennis Heihoff https://www.youtube.com/watch?v=nEt06LLQaBY
Perhaps the macro facilities are also convenient but that is not the part that makes Lisp mathematical, it's the higher order programming.
And it needn't even be something fancy, just being able to have a data table of tests and have the test functions generated and executed from the table is the power demonstrated.