Comment by chriswarbo

> part of the problem with the entire "XML as a savior" mindset of that earlier era

I think part of the problem is focusing on the wrong aspect. In the case of XSLT, I'd argue its most important properties are being pure, declarative, and extensible. Those can have knock-on effects, like enabling parallel processing, untrusted input, static analysis, etc. The fact it's written in XML is less important.

Its biggest competitor is JS, which might have nicer syntax but it loses those core features of being pure and declarative (we can implement pure/declarative things inside JS if we like, but requiring a JS interpreter at all is bad news for parallelism, security, static analysis, etc.).

When fashions change (e.g. XML giving way to JS, and JSON), we can end up throwing out good ideas (like a standard way to declare pure data transformations).

(Of course, there's another layer to this, since XML itself was a more fashionable alternative to S-expressions; and XSLT is sort of like Lisp macros. Everything old is new again...)