> Google actually knee-capped the web with the WHATWG's focus on less semantic documents.
There's one teensy problem with your thesis: Google came late to the WHATWG.
The WHATWG started initially as a joint Mozilla-Opera project [1] to basically standardize what you had to do to parse the crap that passes for webpages (including de-facto standard behavior for DOM at the time). At the same time, it also included a variety of speculative features to push the capabilities of the web forward: <canvas>, <audio>, <video>, not to mention Web Forms (eventually morphed into all the nice, new <input> types). It even had semantic elements: <section>/<header>/<footer> originate from WHATWG, after all. Not to mention microdata, too.
Google Chrome doesn't come out until 2008. XHTML 2.0 is put out of its misery in 2009, but that the WHATWG was now the driving force in HTML innovation was clear by 2006 or 2007, by virtue of all browser vendors focusing on WHATWG HTML support and not W3C XHTML 2.0. The W3C tries to regain relevance by staring from WHATWG HTML instead of XHTML for HTML 5 in 2007.
[1] Apple was also involved very near the beginning, but I don't know to what degree it was involved.
Oh of course, Google didn't have a horse in the race for the application web at all until 2008. Except wait, they had released GMail in 2004 and Google Maps in 2005. In fact, WHATWG made frequent references to GMail and Google Maps as examples of the application web and deficiencies that W3C was not addressing in its XHTML standard.
Then Ian Hickson, the main editor behind the WHATWG HTML5 standardization process, went to Google. One of my favorite quotes from Hickson about the whole process (as I noted in a sibling comment):
"The Web is, and should be, driven by technical merit, not consensus. The W3C pretends otherwise, and wastes a lot of time for it. The WHATWG does not."
This says a lot both about the outlook of the WHATWG of the time and the way the development community of the time saw web corporations at the time. And now we have 2 major browsers as of this writing. It's funny how much flak Berners-Lee gets over his acquiescence to DRM and yet the WHATWG discussions of the time are completely glossed over. I was fairly young when the WHATWG and W3C power struggle occurred, but it was a great lesson for me as a teenage programmer in the power of value capture.
There's one teensy problem with your thesis: Google came late to the WHATWG.
The WHATWG started initially as a joint Mozilla-Opera project [1] to basically standardize what you had to do to parse the crap that passes for webpages (including de-facto standard behavior for DOM at the time). At the same time, it also included a variety of speculative features to push the capabilities of the web forward: <canvas>, <audio>, <video>, not to mention Web Forms (eventually morphed into all the nice, new <input> types). It even had semantic elements: <section>/<header>/<footer> originate from WHATWG, after all. Not to mention microdata, too.
Google Chrome doesn't come out until 2008. XHTML 2.0 is put out of its misery in 2009, but that the WHATWG was now the driving force in HTML innovation was clear by 2006 or 2007, by virtue of all browser vendors focusing on WHATWG HTML support and not W3C XHTML 2.0. The W3C tries to regain relevance by staring from WHATWG HTML instead of XHTML for HTML 5 in 2007.
[1] Apple was also involved very near the beginning, but I don't know to what degree it was involved.