Mainly a matter of "all the cool kids are using Racket for DSLs", more seriously the web sites, documentation, YouTube vids, Q&A's etc. say that one of Racket's specialties is writing DSLs and languages. I've used Lisps in the past and I can see how they can be used to turn their internal representation, S-expressions, into XML. In my case it doesn't need to be performant. I'm turning one file format - my language, starting with S-expressions, then a more palatable syntax - into the XML that will be uploaded to Salesforce.

I see, thanks so much for the detailed comment. I will check out Racket. Heard about it but didn’t look into it in depth.