The web may be the future, but (hopefully) web browsers are not. Proprietary applications with embedded web services provide a vastly superior user experience, and that matters. For the record, I was developing 'web applications' in the 90s when it was CGI+Perl and then Java applets. I will be happy the day that the web browser as an application platform finally goes away, even though I know that probably won't happen. Browsers are great for discovering new content and services, but not for user interactions.
Among other things, SunSpider claims to test ray tracing and AES encryption. And gets them done (although it's not clear exactly what it does for each) in some tens of milliseconds. I'd say that puts it well within the realms of reasonable desktop application performance.