Not only that, they're using a heavy amount of tradition. They can't just do any random thing even if it tastes good, unless they're experimental modern types,

Not only that, they're using a heavy amount of tradition. They can't just do any random thing even if it tastes good, unless they're experimental modern types, because Italian has to be different from Mexican or people will wonder what is going on. Most people seem to like the current nationality based food traditions. It lets you celebrate your own heritage, and also explore others. We can make things healthier, add variants, make vegetarian versions, etc, but not many see to reinvent Italian or American Chinese from scratch.