Well... perhaps it's an area that requires more capital than yc style startups - many of those writers probably wouldn't know where to start in terms of putting together some kind of startup.
Or, maybe it's just a ploy to make the studios nervous.
They're not talking about straight web applications, they're talking about using the internet as a new distribution method. The financial requirements of filming a TV show still apply, no matter how it's distributed, so they obviously need to to negotiate with investors to get the money for something like this.
If the buzzword "web 3.0" could be applied to anything, it will probably apply to this kind of stuff.