1. He's still earning ad revenue from existing installs.
2. In the last 22 hours of the app's existence (when he announced
he would be taking it down) more than 10 million new people
installed it.
In other words, he's likely making just as much if not more today. He could have instantly removed it from the app store instead of saying "in 22 hours", so it's entirely possible that he's way better off due to all the publicity and attention from the app's removal.
Yes, quite possible he managed to snatch the last boost from an app that would otherwise have met a decline. It was already being covered all over the news. Reporters were looking for something more to say about it and he gave them that chance. Instead of being featured all over the news once, he got one mention for the initial spread, another one for the takedown threat. Now as a final (?) third one he achieves cult status for the game, increasing replays for the already installed base and ensuring interest for his future games.
I'm sure everything he says is true and it is not a conscious strategy, but the end result is the same.
