[braythwayt]

> The advantage of the regularity isn't its human readability, but its ability to macro, no?

This.

You can write macros for less regular languages, but there's always additional friction involved. At some point, it comes down to whether you think LISP is a "programmable programming language."

If you do, macros are a core part of the paradigm, and s-exprs make macros easy to work with.

[kazinator]

I already really liked Lisp's syntax before I learned about the macros.

No ambiguity; no brain cycles required to work out what element is a child or sibling of what element. Great editing ergonomics.