In my view what happened was that the preparations were made on the possibility that Irene would hit the NYC area as a cat 3 or 4. This possibility became a presumption and then doctrine. The driving rationale was that the public had to be scared into taking the storm seriously. After landfall in NC, though, Irene started winding down, and the scenario that drove the more drastic preparations, in particular the mandatory evacuation of 300,000 in NYC, was obviously not going to happen. Well, no one knew exactly how bad it would actually be, and the need to support public policy became the overriding doctrine, so the facts of the storm’s decline were simply not reported even though they were easy to see.
In addition to this, we had Obama and FEMA making political hay out of the whole thing, and the result was a media conflagration of historic proportions.
So yeah, it was a bad storm with lots of damage, but the reaction to the “hype” is legitimate and nothing to do with hindsight.