The "big deal" is that this idea is hurting art and creativety. To me this idea of forced diversity that OP is presenting is when a characters single defining trait is their race, gender, or some other similar descriptor you can imagine. It means that their is only one answer to every question you could ask about their personality or background. What is your motivation? I am a black guy. What is your story? I'm a black guy. What are your life goals? I'm a black guy. What did you eat this morning? I'm a black guy. This issue is also related to cliches and sterotypes. I dont understand how anyone can agree it's ok to make lazy "important" (some background characters need to be weaker to make the main characters look better) characters like this without taking the time to actually develop them with meaningful personality traits and whatnot. And that's not even talking about the various social issues that could be discussed or about how its EVEN MORE bigoted to create characters in this fashion.