Where's your argument ? You can make the worlds best services/apps in the web browser, that doesn't mean it's the de facto.

Also a chat app or any of the other fancy webapps we see here does not fit into the definition of a web browser https://en.wikipedia.org/wiki/Web_browser

The context of this discussion is wanting to make the mobile browser a suitable platform for development of all apps similar to what has happened in the desktop browser. One of the reasons for this is that the web is one of the few truly open platforms. That it doesn't fit your opinions about what belongs in a web browser is not very interesting, especially since you're not giving any reason why you think some apps should not be in the browser.