I think that many people are drastically underestimating the effect this may have on the open web. The response "oh, well we'll just build a browser that will avoid the DRM" isn't going to work quite as well as one might hope. It's not such a stretch of the imagination that content providers will detect such browsers and refuse to supply any content at all. This would be similar to what many sites do now for users of IE6-8, where a message is displayed prompting them to upgrade. Except in this case a message would be displayed telling you to download an effectively locked-down browser. Ugh.