There is a standards-compliant way to deliver video. It's not streaming, but their use doesn't require streaming. There's, thankfully, no web standard for DRM.
Just to be pedantic, I experience technical issues with HTML5 playback in Chromium 17 on Linux. The video seems to be playing at 1.5x speed, and sound is extremely choppy. Flash works fine.
The support for the audio and video elements in browsers is still rather basic and unreliable. Shockingly enough, in my experience at least, IE9 has the best support for HTML5 audio / video, with Safari on OS X (not Windows) being second best.
There's certainly a technical factor here, even if the media ecosystem is also to blame.