Black gangsters never had the inroads to government and law enforcement that Italian and Irish gangsters had. Jewish gangsters were affiliated with Italians so that was their 'Get out of Jail Free' card. The reason Black gangsters were never able to form an organized crime group similar to Cosa Nostra is the same reason Cosa Nostra never caught on in the west coast, despite the area being ripe with money and corruption. They were shut out by government officials and law enforcement. In NY the Italian gangsters had Tammany Hall. In California they had redneck Willie Parker who thought Italians were just another minority. Black gangsters were met with this roadblock nationwide.
Also another major reason,perhaps the biggest, is that their originally an exported criminal society. They been active since prior to the Civil War unlike the Jewish & Irish criminal associations.
