I just asked a very subjective question about Evangelion (Is the Evangelion Remake a remake or a sequel?) to with I really want only opinions and not really a concrete answer. So I would have liked to add a discussion tag to indicate this. Why doesn't Anime & Manga manga have one? I know from personal expience that a lot of questions about anime are more oppinions than factual question with factual answers.
And maybe it is just me, but a cold Q&A like SO would be kinda dull. There are times when you simply want and oppinion and there are times when you want an answer. Especially for something like Anime and Manga. Taking into considerations the reaction to this question (Should we explicitly allow discussions?) I think it would be well worth it.