Look, I was there. In 2003 post dot-com the web was still very static and very transactional. It had become uncool and was perceived as being quite stale. Microsoft had implemented this proprietary extension that was mimicked in other browsers but nobody was using it. Dynamic HTML as it was known back then wasn’t catching on precisely because there were so many incompatible variants. Google was the first large company for some years to start pursuing talent purely on technical merit, they put these in a room together and the opportunities were recognised. Up to that point XMLHttpRequest was an unknown proprietary browser extension. Google used it to inject dynamism into gmail in a way that was never evident in Outlook. This was the genesis of Web 2.0 and everybody started scrambling to use the browser as a platform again. The web was cool again.

EDIT - despite what they may have become, and despite the many ways that the web has been “broken” since, we have so much to thank google for.

EDIT - so hard to believe this all happened 15 years ago. It’s ancient history at this stage, but seems so recent to me.