So I have finally found the time to actually read this blog in more detail and I think DHH is right although he is ripping into TDD a little too much. Probably because of his desire to change Rails in some way.
The current trends in the industry are moving towards SPAs and JS, much more closer to the user, since software is no longer seen something large scale banking organisation do but more something that everyday people interact with. So by this reasoning SPA and client side application are naturally going to be growing. Currently client side frameworks like Angular have in built system or acceptance testing like Protractor, which test the application as if the user were doing something. This I believe is the next evolutional trend in testing because again we are closer to the user and we are what the user will see, which ultimately in this era of software is the most important thing.
I get the feeling DHH is about to include a Acceptance testing framework somewhere in the next Rails version, and since frameworks like Angular are already a head of the game, he might be trying to cover his back with a bit of PR though I might to wrong.
Nevertheless I do believe we need to move to more automated front end E2E testing like Protactor or Capbyra.
Long live testing!!