Everyone has their own syntactic preferences. And what, really, is the difference between a preference for certain colors in an IDE and a preference for a certain syntax? Why is one easily customizable and the other rigidly defined by a language? If programs in all languages were stored on file as lisp-style AST's, with comments attached to AST nodes, then programmers could view programs using their own preferred syntax, as well as formatting and colors.
The pure version of this idea has failed repeatedly for more than 50 years — noone ever writes their code in M-expressions :)
A debased version of the idea found success in Haskell, where the language syntax is defined as desugaring transformations towards a core calculus, but the internal representation is implementation-specific, and since the syntax was decided up front nobody got invested in writing code in a plain System F.
A novel take on the idea is implemented wholeheartedly in Google's Go, where there's a utility based on the compiler called gofmt that reserializes the AST. They use it not only for style issues, but also to update the entire standard library to reflect syntax changes.
