As a strong supporter of open source, doing a comparative analysis of HTML5 and Flash, I have to admit that private enterprise was able to kick the ball forward so much faster here ...
I remember watching a vector animation version of a "tell-tale heart" in flash in 1998. On a 28.8 connection it played smoothly full-screen on a 120mhz pentium with 16mb of ram. I remember clicking the play button and having it just miraculously starting to play without any wait, streaming down and uncompressing in real time. I was floored by it. 12 years later I was invited to watch a spiderman animation demo using HTML5 ... there was a 30 second load time, the framerate was probably 1fps, the audio didn't work, the content didn't render properly ...
It's like how Microsoft was able to pull off nearly everything we could do today by shoe-horning their activeX technology into ie3. Just load a bunch of cab files and drop them into the page like OLE components and bam, you got just about everything. The interactivity could bootstrap - that is, not need any extra plugin and you could engage with the other content on the site using vbscript or javascript interfaces in a two-way manner. It was pretty nice.
Netscape retorted with their JVM integration but it just wasn't the same ...