It’s less that the stereotype isn’t true and more that it applies to everybody. American stereotypes are widely based on racist enforcement of laws. Obviously there are italian crime families, but there are white crime families like the Sacklers that do far worse shit, but we don’t stereotype white people as criminal masterminds. Italians are considered white in America now though, so they have less stereotypes attached to them.
If America was less racist, you wouldn’t hear about country of origin in crime. I’ve had people of all races sell me cocaine out of the back of the sketchy restaurant.