Seems a bit odd but it hasn't been confirmed yet. I don't play these games in co-op though so it doesn't really affect me. I'm going to go on a media blackout until the game is released but for those that don't, I think it might be better to wait for proper gameplay previews before making any assumptions. I've heard rumours from people I trust on other forums that this game will not be a defacto Dark Souls 4 and will be quite different from what we're used to.