User blog comment:Cristina7/Introducing Discussions, a New Platform For Engaging Your Community/@comment-26408193-20160908195752/@comment-1370845-20160908225624

You don't have to care about it. If you're not interested in the offtopic fan discussion, you can just pretend it doesn't exist and let someone else who uses it moderate it. If you want to have wiki discussion on Discussions, you can still just put them in one category, filter to only show that category, then ignore everything else. So in that sense, it is optional.