But that statement implies that he never should have made The Godfather Part II. It's a controversial statement considering how highly regarded Part 2 is. Shini, you're normally on point but I'm not sure what you're getting at here. The only way I agree with you is if Francis meant "There should have only been one (sequel)." From the context it sounds like he was talking about the series, implying that he meant there should have been only one film.
If I don't make off statements now and again I will lose the audience! Huzzah!
The article says he was asked this question by a TMZ cameraman, right. Which suggests to me the question was in passing and the answer followed in spirit. The amount of thought put into the public response probably doesn't match the amount of thought put into the statement itself. A TMZ cameraman asked if he would return to the Godfather series, and the director, as I imagine him in my hipster mind, said nah bro, it should have stopped at one. That could be a sudden condemnation of the godfather 2 and 3. Or it could be an unmeasured response to a question asking if the godfather series could continue.
But I did get annoyed in a theatrical way at the theatricality of a thread quoting "the godfather 2 was a mistake" despite that, apparently, not being a quote at all. It's an implication, but only an implication.