In the genre tag selection dialog, it says “Select a tag from the dropdown or type to create a new tag.” but when I type in a new tag, it tells me that it’s added as content tag. How would I add a new genre tag?
In case you wonder which one that would be, I found that for non-fiction there are not many genre tags that can apply to them, so I wanted to add “Interviews” for アンダーグラウンド | L33.
If I remember correctly, there was a lot of discussion about what should constitute a genre tag and what shouldn’t, and people tended to have strong feelings about it. In the end I believe it was decided to keep genres “clean and tidy” and allow users to only add content tags. I tried to find a reference to that (I remember it so clearly), but this is the best match I could find:
I’m sure there’s something more official somewhere?
Of course if users aren’t allowed to create genre tags, the UI shouldn’t be misleading about it, I agree. 
I was not sure what the verdict was in the end (I remember that there was a bit of a back-and-forth discussion around it) but if I can create one but not the other, then the UI should be different for them.
There was a bit of discussion in the background with the tag managers (or whatever we are called) as well and at some point genres were logged and the discussion died, I think.
Personally, I’d just mash all the tags into 1 and not distinguish between genre and content (and potentially just add something like non-fiction in the description - since descriptions are searchable), but that’s just me. media type, genre tag, content tag, … lots of classifications going on.
