Another reason is that there is no one drop rule in latin america so you have people who would classified as black in the US but see themselves as just latino
The one drop rule somewhat united the direct descendants of african slaves in america, since they were being disenfranchised because of their ancestry. They wanted the same rights afforded to whites and came together because of their shared struggle and blackness. That camaraderie and quest for justice spawned a lot of the progressive black movements in the US. That hasnt happened really in most latin american countries.
Nationalism is much more emphasized than race in latin america. There has been a concerted effort to push the narrative of a colorless society by latin american governments. Hence the whole "I'm Dominican, Puerto Rican, Brazilian, Colombian, etc not black"
