An everyday example is the difference between JSON.stringify(data, null, 2) and a pretty printer like ipython or Deno.inspect. Having only one node per line reduces the amount of data that can be displayed. It's the same with code.
Recursive teXt (RX) would be a great fit for Lisp, although I am more interested in replacing Lisp entirely with a simpler language rooted in abstraction logic.
Note that RX is not like normal semantic white space, but simpler. It is hard coded into the text without taking its content into consideration. RX is basically nested records of text, making it very robust, but encoded as plain text instead of JSON or something like that.
> S-expressions are the simplest way to linearize a tree.
S-expressions are one way to linearize a tree.
Now, "simple" can mean different things depending on what you are trying to achieve. RX is simpler than s-expressions if you prefer indentation over brackets, and like the robustness that it brings. Abstraction algebra terms are simpler than s-expressions if you want to actually reason about and with them.