My Italian born father-in-law insists pizza is better in the US than in Italy.
It's the same problem that crops up when foreigners proclaim that American chocolate is horrible. Which of the countless different domestic brands? They think Hershey's chocolate is the primary chocolate Americans can buy, it's amusing. The same thing happens in discussions about cheese.
It stems from most nations having small consumer & manufacturing economies, small numbers of suppliers of things. It makes it difficult to understand or relate to the enormous scale of the US consumer market (so large it produced Walmart, a $523 billion sales behemoth that is as big as the economies of Poland, Belgium or Sweden). The only proper consumer & manufacturing scale references are to the entire EU or China. It's almost the equivalent of saying pizza in the EU is good or bad; or cheese in the EU is good or bad. It would make absolutely no sense.
Even pizza in New Zealand, when I lived there, was significantly different from American pizza. It's closer to American pizza, but Kiwis really love to use tangier sauces, which for some reason they also drizzled on to the pizzas. They even did this at Pizza Hutt.
Everywhere has regional differences. To claim otherwise is a bit blind, in my opinion. Just because American culture is mainstream doesn't mean that it's not distinct from other cultures it's related to.
That ain't the comparison being made, though. American pizza doesn't stop at Pizza Hut or Domino's. It includes the hole-in-the-wall pizza parlor with generic boxes and the ever-so-creative name of "New York Pizza". It includes the boutique shop with a proper stone oven and the thin crusts and "traditional" ingredients you'd expect from an "authentically-Italian" pizza. It includes hip vegan pizzas with cauliflower crusts. It includes pizza served alongside - or even incorporating - curry or kebab (side note: if you haven't had butter chicken pizza, stop what you're doing right now and find some). Hell, it even includes the "Bahn Mi'zza" I had for dinner a while back.
There are, in all, 70,000+ pizza restaurants in the United States, and that's just the ones that focus specifically on pizza - i.e. not including "Italian" restaurants as a whole, and not including restaurants that serve pizza as one component of a broader non-pizza-focused menu. All said and done, you've likely got more than a hundred thousand restaurants each putting their own spin - subtle or drastic, intentional or accidental - on the phrase "American pizza". That's in the ballpark of a 10:1 ratio of places serving pizza to incorporated cities/towns/villages/boroughs in the United States.
Point being, American pizza tastes - and thus the restaurants catering to those tastes - are so varied that "American pizza" v. "Italian pizza" ain't exactly a useful comparison. Same with Italian tastes, for that matter; not all Italian pizzas are the Neapolitan ones you're describing (prime example: Roman and Sicilian pizzas both feature thick crusts). Even regional comparisons are fraught with peril, but that'd be at least closer. Pizza is, fundamentally, a canvas begging for a painter to express one's creative vision upon it, be that a celebration of tradition or an exploration of new tastes.
If you drive around the US and visit pizza places on the way vs doing the same while driving around Italy. If you go to the main US supermarkets and pick up an assortment of different US chocolate brands to try vs doing the same in, say, Belgium.
There is no good mass market American chocolate, but there is readily available access to gourmet chocolates and pseudo gourmet chocolates.
Chuao Chocalates comes to mind as having frequent distribution and can be found in many places, Sees chocolates is fairly easy to find and has been around for a century,it gets mentioned on cooking shows so I think it has some prestige/familiarity to it.
Gertrude Hawk chocolates exists in many eastern us malls (maybe elsewhere), it's made not far from Hershey park. The samplers arent bad, never really gave it a proper try.
I happen to like Godiva chocolates which is owned by Campbell's soup company and also has a factory near Hershey's but that is maybe nostalgia as I often purchased them only around Christmas and rarely even consider buying them now.
Ghirardelli is American and Theos chocolate has some esteem.
By conventional meaning of mass market, I believe only Lindt and Ghirardelli qualify and fit the description of "good"
I recently tried Callier chocolate which I read had quite a prestigious swiss heritage, it blew away any mass market Hershey/Mars "chocolate" bars but it wasnt particularly exceptional compared to similarly priced artisanal chocolates already available in the local grocery store.