I mean semantic web is designed to turn the entire web into a semantic database. You could treat "your" parts of the web as DSLs in the simplest possible RDF/linked data and then link it to semantic web concepts (and other people can link it as appropriate), but I don't think you can create anything like a semantic web with standalone DSLs.

> That is what I was saying. Layouting and rendering general case graphs is a mess.

Yes, unfortunately and somewhat ironically since the web is a non-tree graph.