DRM gains traction from people buying services that use it. It's that simple. If there's enough demand for a Netflix-like service in an ecosystem where only one browser does DRM, a company will spring up that provides such a service only for users of that one browser, even if it's a relatively small market. But, as it happens, watching digital content over the internet is a huge market, so every browser is going to have DRM built-in whether there's a standard or not. The market is big enough to support many different DRM mechanisms (we can tell that by the fact it already does).
Consequently we have to accept that DRM is going to exist whether we (the technical "elite" who understand the issues) want it or not. If we want an internet where DRM isn't entirely pervasive, where video will work without being DRM'd, where it doesn't spill out in to things like only running "signed HTML" or something horrible, we will need a decent standard that people on both sides of the debate agreed to on a pragmatic level if not an ideological one.
I believe that a W3C sanctioned DRM is a hell of a lot saner than Microsoft, Google and Apple coming up with their own systems.