I'm not arguing against providing a decent notice to people who's browser set up is not compatible with the technology being used by the application. I believe that, where possible, elements should provide support for people who's interaction with the web may be limited whether by physical disability or some other limitation. I'm not advocating dropping semantic tags and serving all text by inserting it into the dom, I just believe that the web is moving beyond being simply a platform for disseminating static content and while that remains important we should not let it hamper efforts to evolve the web as a platform for new technologies and uses.

I suppose I should have more verbosely indicated the facetiousness of the first few rhetorical questions but they do serve a point.