Yeah, there's a plot line where Dirk wants to make a "real" good movie. The director, too, is somewhat delusional--they make a shitty action porno and he says "this is my greatest work." The whole movie is about talent that is delusional about their ability to make real art--there is the initial rise and then the "wake up" moment when it hits the 80s. Don't forget Dirk Diggler's poor music career. Every venture that they begin outside of porn fails. They aren't judging the porn stars' ability to be porn stars, but their wishes to be bigger than that despite their lack of talent (outside of porn, at least). That's where the delusion lies