One of the benefits of a single maintainer is that they can say 'this is my definition of these technical terms and if you don't like it you can go suck a lemon'. A Wiki will quickly devolve into endless bickering over what really counts as 3D and where the boundaries of certain genres lie.
Using some random individual's definition of something is rarely useful. If that means things can't be neatly fit into a list, so be it. On top of that, knowing that there is an open discussion around a topic is, in and of itself, usually useful to understand as well.
