Tuco, I rue the day you and are opposite sides of an issue. Luckily, in this instance we are both on the side of objective truth.
I find the "less is good enough" position baffling. Why would you use EA time to say "good enough"? I mean really, it take me back. You can't argue that 4 feels like BG. You can't argue that 4 is ideal for D&D and the can't argue that give you more content. The closest thing to argument is repeating what the devs had said "combat last too long" but I don't think that's much of an argument. Or isn't one at all. With 6 parties you can use different strategies, combine the strengths of different classes and *even if that all seems wrong* you can still just take 4 along. But it wrong as anyone who tried the mod knows.
My honest to goodness best guess is that "4 is fine" sentiment springs from a desire to side with devs and show that you know how video games work. I really can't think of another reason.