But again, the fact that they don't want people leaving WZs early means they don't people stacking queues. Because the reason people are leaving WZs early is the FP queue pops in the middle of it.
I just don't think we can assume that they don't want us to stack queues because they disabled it. There is obviously a problem with people leaving in the middle of wzs due to a lfg pop (after sitting in lfg queue for 2 hours, it's understandable). They decided to quit allowing stacking because of this. That doesn't necessarily mean that they don't WANT to allow stacking, just that thus far they haven't found a way to do it that doesn't negatively effect wzs.