I'm a bit of a pizza snob myself, and I feel like I live in a pizza desert. I'm near DC, and there's a ton of pizza places. The problem? All of them are either crazy expensive, or they're trying to create a high-end type of feel for pizza.
But to me, and I suspect to a lot of others, pizza isn't a high-end food, it's a comfort food. I grew up in a rural area where there was a single local pizza place that had what I would describe as "generic New York style" pizza. To me, that is what pizza should be. I cannot get that kind of pizza here, and not for lack of trying, as I've tried a lot of pizza places.
Meanwhile, the big name chains don't have that feel either. Dominos is good, for example, but it's definitely something that doesn't scratch the pizza itch. I have to be in the mood for Dominos, not generically for pizza. Same for the other chains.
When I visit where I grew up, the pizza is always top notch, and quite a bit cheaper. My wife and I go out of our way to get it on many of our visits. But here? I end up on frozen pizza much of the time when I want pizza because it's cheaper and just as fast as delivery much of the time, and if you're picky, just as good as local delivery. (And my wife started making pizza, which is also really, really good.)
It wouldn't surprise me if things like this are driving down the interest in pizza. In chasing the top end, they're abandoning the much larger low end. At least, that's what it looks like to me.