[Hixie]

> Flash apps were also "true web apps"

Not really. They were not portable. NPAPI was not a web standard in any meaningful sense (hint: the first N stood for Netscape).

> That's why there has never been a UI toolkit as successful as the web.

The web's success in terms of active users and in terms of deployed content is astounding, certainly. I think I'm relatively well placed to understand why, and I don't think it's because the web restricted developers to one scripting language or one set of controls. I think it is very much _despite_ that.