Hear hear. I think of all the romance languages, italian is the hardest to learn because grammatically it's such a tricky language. It takes so much concentration to get everything in a sentence correct, and in the right place!
Spanish and French are IMO easier to learn but difficult to sound authentic in - but italian? I can't ever imagine being able to pass for a native in Italy the way I can in France.

When I was in Sicily I was painfully aware that I must have stuck out like a sore thumb for speaking Italian to people who responded in a dialect. I mean, they understood my Italian, but I only understood about half of what they said back, because it was in Sicilian.
I guess it's like accents in Britain. People who learn english as a foreign language here are encouraged to speak with a BBC accent (standard pronunciation) but in fact only a tiny percentage of people have that accent. Everbody else speaks with some degree of strong regional accent, which it's practically impossible for a foreigner to pick up accurately.

As for Anthony though, I think we underestimate the power of imitation by ear. It's unusual for popular english speaking singers to have to learn foreign lyrics, but abroad many popular singers have to release english songs to widen their audience. Many of them have very little knowledge of english. I don't think it's unbelievable for Anthony to learn lyrics in italian, given the libretto, rehearsals, and a basic knowledge of the language picked up from his relatives and his short time in Palermo.