Dragna/Milano's structure are gone thats obviously. "
"There are no Italian communities " does not explain why they stop recruited new members. Again the mafia don't need communities. It's a simplification to think mafia only existed in italian neighberhood.

So may guess is young criminals don't need a fix structure to make money. Culturel mixed groups are more powerfull. But again we don't know much about OC in Cali.