We stopped having an NA server for NW year or so ago. It wasn't worth having one up. At this point, i dont really see the need for us to host one either. Our CB server was more popular than the battle server at the end. Most of the people that pub played before we took the NA server down were in the various bot servers.
I don't blame people for wanting to play on those servers. You dont have to worry about tryhards or veterans slaughtering you. The bots just suicide into you while you camp. Perfect for casual players. CB is CB, which can always be fun.
As others have said, if people really wanted to play battle again, they would host their own.
We will have an NA server for BCoF. Though if i had to guess, Conq will be more popular than battle.