> Are there many applications these days which are not available as a "web app" aka website?

I hope you mean "are there many application these days which cannot be replaced with web app". The majority of desktop applications are not available as web apps.

I'd say the majority of several dozen applications I use on a daily basis could not be replaced with a web app, at least today.

Of course with web browsers becoming their own operating systems, most of the applications could in theory become web apps...