Representation is important. Do you know how many positively-portrayed fat women have been on TV in my lifetime as normal people and not miserable or gross or comedic foils? I can think of two off the top of my head. I understand what you’re saying, that there were opportunities for more depth in the other characters. But that’s not what this show is about, and I don’t think it’s really a downfall that the writers focused on Annie’s story. Looking at how TV has changed over the past 10 years, there are shows with LGBTQA+ people, there are shows with all black casts, there are Asian characters. There are always tropes, of course, but people like Annie are largely completely absent.