Maybe it was unecessary for you. I really thought it was necessary for me who didnt have a main LI so far and I always wondered about Zoey when MC told her story to Bella. I always wondered if she would come back and it was amazing when I played the interlude and end up loving the character. She has history with MC and she has everything to become my main LI. She is part of the story since chapter 2. For me she is extremely important and I want to see how things will play out with other characters. Specially the ones I am kind of getting involved such as Quinn or Sage and I wanna see how Josy will react to it.
I am pretty sure the people who dislike her are not that many, just the annoying ones who have no life and reply to this thread everyday.
He took 3 years to give us a VN that no one has ever seen around. It is not only a story teller game, but it is as well a game. With RPG content in it, minigames, a VN where your choices actually matters and influence the outcome of the story. He has to think and write every detail, Create many fun minigames that are related to the story, make us feel like we are immersing in the life of the character. And has amazing and high quality images, characters has their own personality, animations are top tier, this is all he has been doing over the 3 years and he is THE ONE dev we know that will deliver the whole content. Not like others that will stop at some point or "rework" their game and you will never see the end of it. Just add the fact that he is doing it all by himself. The guy has to be the writer, the coder, the artist, editor, manage his own business, buy licensed songs that will add to the story.
Despite the fact that every character is different from another, they are genuine and unique, not like other games every character in the town looks like twin siblings.