From my own experience over (almost) five years, I have to agree. Art was always kind of a side issue on youtube. There are many underrated artists here, many who want to reach out to more people, to get other people involved in their work. Youtube needs an art category to make it easier for interrested people around the world, to find our work - get to see it, and get a better chance to respond to it!
Thanks for starting this. I hope, there will be many others, who will follow!