I am completely aware of that. In fact this is from the interview where he talked about it
AVC: It’s hard to imagine there’s any other actor on IMDB who can compete with you when it comes to the number of films you reportedly have in production.
ER: Oh, you know what? I’m gonna tell you a secret: They aren’t all real. What happens is, when they offer me these movies, they then put them on IMDB as if I’ve said yes, to attract other actors. So it’s all a show-business game that goes on that you just have to live with. It would be impossible for anybody to be in that many productions in the same year. Impossible. But I make a lot of movies, and I work probably 200 days a year, at least, so I am a heavily working, thankful actor. But I’m not a superhero. [Laughs.] I couldn’t possibly do all those movies.
Regardless, he's still in a shiitload movies. Out of all those projects listed, Roberts still does a good chunk of them. The guy is a beast. He seems like one of those guys that stay up 24/7 obsessed with making working & making money. He'll fly back & forth between projects & do them at the same time. He works as if he's trying to stay out of poverty.