For reference, I just wrote about coming from a blue collard family as a first gen college grad and having to navigate the academics and whatnot without much help. That and having to work summers and many weekends helping my family with our struggling contracting business. These are "first world" problems I guess but I feel confident about adding ~300 characters describing where I come from and how it has allowed me to grow and differentiate myself from other more "privileged" candidates since its not really addressed elsewhere in the app. I don't think you have to write about being homeless, being a foster child or anything like that.
All that said, I also think its fine to leave it blank if you are unable to write about something without coming off as "woe is me" or if it doesn't really add anything to your app.
