I've never used a Lisp either, but I get the impression that "forcing you to write the AST" is sort of the secret sauce. That is, if your source code is basically an AST to begin with, then transforming that AST programmatically (i.e. macros) is much more ergonomic. So you do, which means that Lisp ends up operating at a higher level of abstraction than most languages because you can basically create DSL on the fly for whatever you're doing.

That's my impression, at least. Like I said, I've never actually used a Lisp. Maybe I'm put off by the smug superiority of so many Lisp people who presume that using Lisp makes them better at programming, smarter, and probably morally superior to me.