Yeah, horse shit. I've had brands that use way less air in the bag and they weren't destroyed, and I remember a time when companies in general didn't use all the air in the bags and we weren't getting bags of dust back then.
Old tasting no. It's not the nitrogen that keeps them fresh, it's the lack of Oxygen. It will of course keep them from crumbling to pieces though and that's enough of a reason.
I recently saw a local brand of chips with the tagline "less air, more chips", and hey, there it is, capitalism at work. Competition happening.
Then I remembered that PepsiCo owns Frito-Lay and they are a huge conglomerate, so it doesn't matter what it says on the bag. And hey, there it is, capitalism also.