Mario is Italian not American

Mario doesn't exist. Mario is a fictional character, depicted as an Italian-American, thought up by a Japanese person. Why are you so angry over it? Oh yeah, that anti-Americanism that bedevils your entire sense of reality and now resembles a full-blown mental disorder.

must you try and claim him like you try to claim pizza (Italy)

I've never heard an American say that we invented pizza.

Meanwhile, you Brits always claim that you invented the internet, which is an American invention. You also have a lot of pride in your rock bands that have historically just straight up stolen their music from and imitated American blues/rock musicians.

nationalist historical revisionism

Ironic coming from a Brit.