I don't have a lot of good insight on this. You'd be surprised how little interaction I had with the IC PTB on any type of consistent basis. Most of the discussions I had with the PTB were because something had blown up and I was kinda in the way of fixing it.
My hunch is that they knew there would be a cost to closing down the ZZLP and they were willing to bear those costs. In the long run, it was certainly a smaller cost than continuing to lose posters over political discussion over a longer period of time.
I have no idea if the immediate reaction was larger or smaller than they anticipated.