It’s the speed of change that suggests it’s more than just the natural evolution of food. I am not saying it’s a purely negative effect, just describing what’s happens when a new ethnic food gets introduced to the American pallet.

I stand by my original point that you can’t call something authentic X after you significantly later what it is. Small town pizzerias and snobbish restaurants are both very distinct from classic Italian food.

That said, if you go to Italy today they very much cater to tourists expecting food their familiar with. Further, while the tomato was only imported in the 16th century, that’s plenty far back to confuse the issue.