I spent a good deal of time researching Traficante's ties to the assassination. Through all the conjecture and (always enjoyable) conspiracy theories there are some undeniable facts:

Jack Ruby visited Santo Trafficante in Triscornia prison in Cuba in 1959 along with Lewis McWillie, a Trafficante associate who worked at the Sans Souci.

Ruby was involved with the Dallas family, esp the Campisis

JOhnny Roselli was heavily involved with JMWAVE and anti-Castro operations in South Florida- he had definite ties to the intelligence community.

The CIA utilized Cuban gangsters in Bay of Pigs and other operations. Some of these Cubans went to work for Trafficante (the early Cuban Mafia in Miami).

Trafficante was "hired" by the CIA to kill Castro.

JOhnny Roselli did NOT kill Kennedy.

THere are loads of more coincidences, connections, and crimes associated with the Kennedy assassination that tie back to the Trafficante,Marcello, and some tangential ties to THe Outfit. It's an intriguing rabbit hole to fall down.

Safe to say that the Mafia, as a whole, did not kill Kennedy. Certain mobsters, however, were neck deep in anti-Castro activities (and possibly pro-Castro spying). The Cuba nexus (including these said gangsters) is IMO the most probable phantom behind the assassination.