[Alastor]

Why does everyone try to make up theories about Dante's personality? It's very simple.

Hideki Kamiya, when he created Dante, he had a vision about his personality, inspired by certain things. The creators of Dante from DMC2 interpreted him wrong, maybe they were lazy, w/e. The reasons aren't story related. People who say that DMC3 Dante can act the way he does because he's young are wrong. Hideaki Itsuno's vision of cool is this really over-the-top thing that the last two DMC games have. Because Nero has it,and so does Dante. It doesn't matter whether or not you like DMC3 Dante or DMC4 Dante, they're still very out of character when compared to the original Dante.

Two different creators, two different games, and different styles.