Yeah, this is a problem especially when arguing "realism" between Dantes.
To be fair, DmC Dante is no more realistic than DMC 1 Dante, he's just younger and has a more modern look. Just switch the two and you'll basically have the same guy with a different outfit and way of speaking. As for DMC 3 or DMC 4 Dante, they aren't realistic at all and DmC Dante is very different from those two. Outside of one- liners, DmC Dante handles things much differently than those two. So saying that the new Dante is more "realistic" than the previous Dante needs some clarification as to which Dante you're talking about.
Also, saying that the new Dante is "cooler" really depends on your definition of "cool" and what exactly defined each Dante as "cool" because each was awesome in his own way. DMC 1 Dante had a "challenger" feel to him and DMC 3 Dante was just... ridiculous. Each one had a different feel to him and so does the new Dante. He's cool in his own right and you can't really compare that to DMC 4 Dante who was a corny type of cool.