Here is one hypothesis:
…some food scientists and market researchers think there is a more surprising reason for the broad nationwide shift toward bolder flavors: The baby boomers, that huge, youth-chasing, all-important demographic, are getting old. As they age, they are losing their ability to taste – and turning to spicier, higher-flavor foods to overcome their dulled senses. Chiefly because of degenerating olfactory nerves, most aging people experience a diminished sense of taste, whether they realize it or not. But unlike previous generations, the nation’s 80 million boomers have broad appetites, a full set of teeth, and the spending power to shape the entire food market.
I’d be surprised if that explained more than five percent of what is going on. Younger people are also preferring spicier food. Western Europe has an older population, but I don’t see them (UK aside) falling for spicy food at a comparable rate as are Americans. Nor does Naples, Florida have much spicy food outside of its Haitian community. Instead America has more immigrants, and more restaurants run by immigrants. Spicy foods are addictive. Most importantly, spicy ethnic food is often better than what we had before, which indeed was usually horrible. Sometimes the best explanation is the simplest one.
I might add that what is eaten is hardly very spicy at all, at least not to my palate.
Thanks to Michael Makowsky, a loyal MR reader, for the pointer.