So, uhh... why not use a notation where nesting is expressed via indentation, then? I don't understand how the syntax can be considered superior if the way people actually cope with it is to hide another syntax inside it.

I was dumping ASTs as part of a little language project recently and my first impulse was to render them as S-expressions. Alas, it just wasn't readable; I couldn't make any sense of it. Indented YAML style lists, though? The structure pops right out and the information I wanted was immediately obvious. There were no constraints here, I was free to render text in any way that suited me; the Lisp style syntax just wasn't helpful.