When I'm building a website for a small business, I'm not breaking any new technical ground. They need an inventory database, product news, search, an ordering and fulfillment system. At the moment, there are a bunch of systems that promise to fill that niche, but they usually still need somebody who knows HTML and CSS if they're going to customize them to any degree. Why is that? There should be WYSIWYG editors for these things. You should be able to drag-and-drop drupal modules into place in an editor, not glue them together with configs and code.
Your friend shouldn't have to know about Ruby or Rails or Agile development. The fundamentals of computer science are as relevant to building a low-traffic website as the fundamentals of chemistry are to baking a cake. Sure, you do better if you know them, but 99% of people can get by just fine by trial and error.
What the people who have CS degrees should be doing is not building websites; they should be building the WYSIWYG editors.