Probably like 98% of the new forum topics are just copied BURs from Danbooru, so if we had one that would combine all of that into one topic, it'd be a huge mess. A lot of the time the discussion has already been done or the BUR is an obvious one to approve (like color tags), but some of them require discussion since we don't always agree with every change that is made over there.
So if we had two or even three non-simple BURs going at the same time, the replies and conversations would get real messy. It's better to keep it separate.