I'm not sure we're meant to have a firm answer to that one, which is one of the reasons I think it's such a great, great film. Taxi Driver by comparison seems to be a much more cut and dried fantasy -- though of course there's debate about that -- but with the King of Comedy the x-factor is that people really do have a tendency to be bowled over by safe, ****ty comedy. I mean, is Rupert Pupkin really a worse comic than Jay Leno?
This is where the interpretation becomes so personal though because I don't think everyone out there is quite so irritated by "safe" comedy and bourgeoisie milquetoast satire as I am. They might view Pupkin as a nutty guy who's fantasy is obvious, or they might even view him as a funny guy who just went too far. Depends on the person and whether they're a target of the movie, as I see the target.
To me he's a first cousin to those poor souls who need so badly to be famous they go on American Idol and actually think they deserve a shot, because hey, people should get what they "need". It's a truly prophetic movie that way, not unlike Network. There's a whole group of people out there who've taken Andy Warhol's comment about everyone having their 15 minutes of fame and turned it into a birthright. It's scary.
I don't watch American Idol because it's too painful, and the King of Comedy to me is similarly excruciating, though in a good way. A great way, actually. It's my second favorite Scorsese movie after Raging Bull. It's been a while since I've seen it. Definitely need to do it again.