It's not that simple. The pre-order threads, presumably, are to discuss and track pre-orders. As in, I've pre-ordered, and I'm showing a delivery date of x, and this other person is seeing a date of y, and the site is down, and the site crashed during pre-order, and my pre-order this, and his pre-order that. Whatever. Hard to have that content three months ahead. Then, when it's actually pre-order time, there are pages and pages of useless babble, continuing through and after the opening of pre-orders when people quote the nonsense and keep the babble going. The result is the entire pre-order thread is trash.
Personally, I do ignore the pre-order threads because they are pointless to me. But whatever utility they have for others would seem to be eroded by having one started months and months ahead of the actual pre-order.