So pizza in Naples is only slightly older than pizza in Little Italy in NYC. It arrives in USA in 1890s
The main problem is that in the great american convenience rush of the 50-s, 60-s etc the tradition is overwhelmed by mass pizza from the chains. And what becomes mass pizza (especially delivered) is inferior product. We have lower baking temperatures, start pumping the dough with oil, sugar and whatnot to get some browning. To compensate for lack of flavor in the dough you start putting all kinds of toppings on top and too many of them. Upping the calories to insane levels to compensate for their flavorlessness.
I think that when people dish out on American pizza they don't mean NYC, New Haven, Chicago or Detroit styles but Dominos and Pizza Hut at their worst.
That's interesting, I'm annoyed at my shortcut/assumption in my head that a) it would be older than 170 yrs and b) that there wouldn't be a clear historical record of the exact date. Although, cooked down tomatoes, flatbread etc. presumably met under a different name before that
Have you had one in Italy? Personally, I quite like American style pizza, but the Italian style I still find has a more interesting flavour profile and therefore I tend to prefer it.