Hey look judging from how this thread evolved in the last several hours, at least it turned out that the bait worked and a bunch of people were dumb enough to take it?
To be fair though, that horse bolted a couple of centuries ago. What other name would you call it by? There's another "united states" on the same continent. The country to the immediate south is formally known as the "United Mexican States".
But the whole hemisphere is not "Mexico". USA and Canada are not also "North Mexico". Their harmless little reminder is more correct than any of the attempted arguments against it.
It was the first group of united states on the continent. North America was, relative to the land that became Mexico, thinly peopled. Unlike in Mexico there was no pre-colonial, indigenous empire that had ruled and named the land which eventually became the 13 colonies. So there wasn't necessarily a better alternative to put after "United States of" at the time. Do you know of one?
The level of arrogance some western-hemisphere Spanish speakers have, trying to tell foreigners that the name they use for their own country in their own native language is wrong, demanding that they translate the Spanish name and use that instead, is so absurdly entitled that it's just... hilarious.
In your world, then, is it normal to complain about other people's names, and expect them to change what they call themselves to better suit your preference?
This is the point: in English, it is not a generic geographic term.
It is in Spanish, though, so I get where the confusion comes from (at least when that confusion is genuine and not just boring troll shit). In Spanish, "América" refers to what in English is "the Americas", because in English we use separate terms for North, South, and (sometimes) Central America.
It's not pushback. It's just dishonest ragebait bullshit.