I think the question is: if you didn't use the web, only library sources, would youy really get a more accurate version, or just one that's better thought out and designed? With webpages, there are virtually no criteria they someone has to fulfill to be able to publish their version. With books, they need money and influence. Not truth.

I think the web just makes something glaringly obvious that people used to forget with printed matter: The truth may be out there, but all you'll ever actually get is somebody's version of it. The web teaches you to be sceptic, and to do your own thinking instead of believing what somebody else wrote. And that is, I think, a lesson even more valuable than all the actual information it contains.