While I agree those were the goals, you don't need XHTML and XML for achieving these. The same is possible with SGML and/or other processors (and xslt can at le

While I agree those were the goals, you don't need XHTML and XML for achieving these. The same is possible with SGML and/or other processors (and xslt can at least generate HTML, too). HTML and RDFa crawling on the web is a thing. Saying as someone who coded a web app with browser-side XSLT and linked data ten years ago.