Modern tomato sauce used in pizza is a variation of the sauce in southern Italy. People were cultivating tomatoes there after they were introduced by Spain, that controlled both that region and the North American lands formerly controlled by the Aztec city-States (nowadays by Mexico).
Where are tomatoes from? South America. Yup. The lands are today Peru's and/or Ecuador's. Likely domesticated way before Cuzco/Inca expanded over the region. In the meantime, the pineapples being put over the pizza are from another region, the Paraná basin (currently controlled by Brazil and Paraguay).
Then you got the dough. Wheat was domesticated somewhere in the Fertile Crescent; I think that the lands currently controlled by Iraq should be a safe bet. In special, Eastern Rome (aka Byzantium) used to control Naples too, spreading πίτα/pita (a type of flat bread) again into the region. (I say "again" because the Aeneid already talks about pizza, in Republican times.)
Cows (for the cheese) were domesticated a bit further to the west, probably what's today controlled by Syria... well, at least one of the times, because you can almost hear haunting zebu moos from what's controlled now by Pakistan. (I believe that most domestic breeds should be a cross between both, with varied amounts of zebu x taurus. And perhaps a third stock from the Maghreb.)
Whats a Canadian from Greece? Was the guy Greek living in Canada? Doesn’t that just make him Greek? Or was it a person born in Canada with Greek ancestry? That would not make him from Greece.
I go to Italy often just to eat real Italian food. I understand that for Italians, the hawainana pizza is an aberration, like many other things if not cooked as they traditionally do. And I respect it, because it's a key part of their culture. Still, I have a right to eat and like whatever I want, so I also expect respect on that sense. Some people will do this and some others won't. I think it's a personal choice to decide respecting others opinions.
Just think, if you open your mind and let other cultures be your inspiration, you too could invent something as reviled and divisive as Hawaiian pizza.
A fruit native to Brazil. We call it "pizza hawaii" in the Netherlands and it's tasty. Ananas, ham and cheese, perfection I say, pizza puritan snobs be damned.