Even if he felt otherwise, as others have said, he has to be very cautious about what he says. His star is not ascendent in Hollywood at the moment. His recent track record with the industry features as it's highlights (starting with the most recent): producing a TV show that got canned after one season (Dollhouse), having a film project pulled out of his hands by the studio (Wonder Woman), and producing one big screen movie that went essentially nowhere at the box office (Serenity). Prior to that, he had one arguable success (Buffy series), diminished because it was shown on a "fringe" venue, not one of the "big four", one mediocre outing that was cancelled before it's natural end point (Angel), and another "one season wonder" (Firefly). His only positive credentials at this time are three moderately successful comic book runs, and that's not going to be enough for a big studio to want to back him. Simply put, he cannot afford to make enemies by bad-mouthing others. Now before everyone starts jumping down my throat to defend one project or another, understand I am not passing judgement on Joss from a "fan" perspective, but from the perspective of a movie/tv studio exec. From that PoV, Joss' track record is far from being a "big success".