American Samoans aren't citizens because American Samoa is a territory, not a state. Puerto Rico has a special status that was extended to it to grant its residents citizenship – this isn't a status that's automatically granted to all territories, it requires Federal approval which AS has never formally pushed for.
> Yet you rarely find anyone giving a shit about the American Samoans, you never hear about it.
This seems entirely subjective.
What a curiosity. It appears that other territories count by statute but for American Samoa the US national designation was created to give them similar rights to citizens but not voting or political office and in exchange the Samoans get some more self-determination than other territories. Cool!