Zion is the developer, while the others are the artist (Kain) and the animator (IND3X), so it makes sense that the developer answers questions and listens to feedback, since he is the one in charge of the story, gameplay and direction of the game, among other things.
I imagine that Zion gives a general direction of what he is looking for in a character (appearance wise) to Kain, who then proceeds to create that character based on those guidelines. Same goes for the h scenes, I imagine Zion says that he wants the h scene to be a certain position or a certain way, and then Kain brings that idea to life. For the animations, I imagine IND3X goes over the variations in an already created h scene, then enhances it by adding movement, visual effects and sound effects.
So while the other members are really important in what they do, their job doesn't really involve many of the things that are discussed or asked here, like the gameplay, the combat, the lore, etc. Even if there was a post concerning their role in the creation of the game, like if someone wants to see a character with certain features or if someone wants to change something in the animations, then it generally falls under the job of the developer (Zion) to decide if he wants to include this or not, and if he does decide to include it, then he himself will tell this to the one responsible in that department.