I don’t get why it always must look the same. If i look at Markdown or Asciidoc/tor, Restext, you get content and formatting. Pack it in a tar.gz and create a directory structure for pages and media, etc. and it would imho suffice. And i would gladly see document X in my prefered font size and family instead of creators favorite.
I mean, i get it for typesetting etc. But not for common use.