It is true that there are several boards with hardly any activity and even, as the OP comments, without activity for years. But considering the general activity of the forum since before December of last year, I don't think it's a cause for concern either. The forum continues to grow, maybe not at the rate we would all like, but it is a fact, so I suppose it is a matter of time before these boards are active again.
I think it is much better to have these boards created from the beginning of the forum than not to have them, at any time there will always be users interested in being able to use them.