Given how long this particular article goes on about how they don't know anything, they're baffled etc., I'm guessing the value of it is in concealing how much

Given how long this particular article goes on about how they don't know anything, they're baffled etc., I'm guessing the value of it is in concealing how much they do know. Maybe an adversary is responsible and they know perfectly well and want to make further observations. Or maybe our own spy agencies are responsible.