What's your alternative? Other countries have similar one-word names for their citizens, "Italians," "Japanese," "Mexicans", etc. United-Statesians? Then we might get the complaint that many other countries are made of smaller states too! Let's go for "citizens of the United States of America," that's nice and short. I get that Central/South America exists, but let us have the word, there's nothing else which sounds good.
Which do you have? Genuinely curious, never used the modern ones, but assumed they’d be shit/very fragile