Most things in Clojure can be found in other languages. However, Clojure has an especially stable and coherent design story, and is quite a bit better thought out than the other languages I've programmed in professionally. The pieces just work together really well, and there isn't a lot of "extra stuff" that only a die-hard specialist would know, or need to. (I currently work at a financial institution, not Nubank, that uses Clojure heavily.)
A few other high points:
- macro-based metaprogramming, familiar to any Lisp-er; macros are essentially functions which write code for you, which allow one to create extremely concise constructs to reduce repetition in code;
- functional programming: probably the hardest thing to get one's head around if coming from a more mainstream language, FP reduces mutable state to a minimum, eliminating one of the biggest source of programming defects and making programs significantly easier to reason about. Additional concurrency-safe state primitives in Clojure makes concurrency a trivial addition to many programs;
- hosted on the JVM, giving interoperability with Java libraries and significant ease of deployment compared to other dynamic languages (I recently went back to Python to roll out a small web service and was amazed at how much more painful the deployment/devops story was compared to our Clojure services).
These are some of the benefits we leverage; other people here more qualified than me have enumerated others. (Plus Datomic, whose philosophy aligns fully with Clojure, though I have yet to use it in production.)
On a personal note, one final attribute I appreciate is structural editing: as a Lisp, Clojure code is data, a feature which one's editor can make use of to allow operations that would be alien to non-Lispers, such as: absorbing nearby expressions or expelling them; splitting them; sorting and reordering; and writing your own automated refactorings without having to write parsers for the language in question. Treating code as data structures rather than strings of characters allows for speed in writing and refactoring code that is hard to give up once you get used to it.