Something similar happens in our sever, 205 (LA). Only 3 groups participate in War. There are still people to do some convoys and plunder but it's still really difficult. We've failed to get the minimum people for Sage Battlefield about 3 times at least.
I don't really know ho it compares to other server, I'm guessing older servers may be in a worse situation, but I still wanted to mentioned it because I don't see the server getting better overtime, quite the contrary I believe.