Fellini refers to Federico Fellini, a legendary Italian film director known for his distinctive and often surreal cinematic style. The word itself is a proper noun, but its use here is highly evocative.
In the song, the line "No, non farti i film, non sei Fellini" (No, don't make movies, you're not Fellini) is a direct and playful jab. It tells someone not to exaggerate or create dramatic scenarios in their mind, implying they're not as important or as grand as a visionary like Fellini. It's a clever cultural reference that adds a layer of wit and uniquely Italian flavor to the lyrics.
The whole song turns on one piece of Italian slang. "Farsi i film" means to build a fantasy in your own head, so when the hook lands on "No, non farti i film, non sei Fellini" (No, don't dream up movies, you're not Fellini), Ernia is calling someone delusional and name-checking the director in the same breath. Kid Yugi runs it again in his verse with "Per favore, niente film, non sei Martin Scorsese" (Please, no movies, you're not Martin Scorsese), then spends the punchline on a rhyme: "La tua ragazza con la gonna sembra un maschio scozzese" (Your girl in that skirt looks like a Scottish bloke).
Underneath the boasting there is an argument about how long any of it lasts. "Non può salvarti un bracciale Cartier" (A Cartier bracelet can't save you), and then the line the song is really built around: "Un giorno morirà pure il re" (One day even the king will die). Ernia picks up the crown image and refuses to put it down. It has weight when you wear it, it is not what people are bowing to anyway, and "In fondo è un cappello da cui passa la pioggia" (After all it's a hat that lets the rain through). He is blunt about his own seat too: "Sto seduto almeno finché il trono mi regge" (I stay seated at least while the throne holds me).