Personally I don’t like sweet mixed with savoury, so no pineapple on my pizza. However in the case of Italy, pizza is part of their cultural identity and many of them would innately not welcome “ foreign “ versions of their pizza.
The tomato was not native to Italy, was brought there from South America by the European explorers post Columbus and the Italians quickly integrated the vegetable into their cuisine with tomato sauce becoming standard on their simple cheese and very thin crust pizza.
Italian immigrants to America took pizza to a new level with the addition of meats, thick crusts and many toppings.
California rolls is often looked down on in Japan because it is a foreign innovation which contains avocados .