I'm not sure that this isn't true.
It's absolutely not true, and here's why:
1. All of this highly secretive, decades-to-rebuild information was exposed by ONE guy with a conscience. From everything we've heard, Snowden wasn't some hacker genius, this stuff was just extremely poorly protected once you got to a certain access level. It's possible, in fact I would say probable, that the exact same set of secrets and more have been removed without authorization in similar ways in the past, but by people with less conscience. From there they could sell them to Russia, China, Al Qaeda, or GIVE them to any number of causes to which they happen to be sympathetic. They may do this either out of greed, loyalty to something other than the US intelligence apparatus, or because they were planted by an external power in the first place.
Why do I think it's highly probably this information has leaked before? Simple: the information was clearly too easy for Snowden to reach, which indicates a fundamental flaw in the NSA security structure... inside any organization, you have to assume that some people aren't what they say. No matter how good your psych screening process, no human system can keep out people with ulterior motives with 100% accuracy -- you have to limit access to only those who truly "need to know" and that doesn't mean broad cross-cutting security clearance levels. It's obvious that foreign governments would be highly interested in information like this, yet Snowden was able to access a huge array of information that he had no legitimate need to access (from the NSA's point of view). Clearly they trust people "inside the circle" far more than they should, which combined with the high probability of at least a couple of successful infiltrations by foreign agents makes it all but a certainty that Snowden's isn't the first leak, only the first PUBLIC leak.
2. All of the public surprise and outrage is coming from people who never bothered to stop and think about the subject before the leak. If they had, it would be fairly obvious that a pretty wide set of things described in the Snowden leak were probably happening. Of course you could never tell for sure, but if you were a little paranoid there were a large number of safe bets you could make, most of which have now turned out to be true. Now, the general public had no specific reason to be paranoid, so they're surprised and upset by these revelations... but they don't matter. This official is claiming that the leak puts them in a worse position compared to the people they want to use these tools against, and (unless the NSA is actually in the business of spying on innocent civilians) anyone they need to legitimately use these tools against is by definition doing something fairly obviously illegal, and would have every reason to be paranoid.
In short, nobody evil enough for the NSA to legitimately want to target AND smart enough to warrant tools this sophisticated is surprised by any but a very small handful of these revelations. And even the ones that are surprising are likely made moot by precautions those people would take against the more obvious NSA tricks.
In short, either the NSA rep is lying, or they really think the people they're hunting are so dumb that they never questioned whether plaintext email over SSL to the GMail servers was enough security to hide them from the NSA, or whether phones registered in their name could be tracked. And frankly, neither answer is good. If they're lying, it's more of the same; and if they really believe the people they were hunting hadn't guessed the majority of this already, then they're criminally underestimating the very people they're supposed to be watching (or door 3, they wanted to watch people who hadn't done anything wrong, and so had no reason to think about this stuff... but they sure do now!)
As an aside, I like how he casually tosses it out like, "yeah, it'll take decades to get back to this level again" as if it were a foregone conclusion that they WILL do that. Of course it's not looking great right now from the public reaction standpoint, but the casual assumption that the nation is just going to sit around while they go install a new network of secret backdoors in all our technology is pretty fucking arrogant.