Let's agree to disagree. I have found citations that support my point. See https://www.britannica.com/dictionary/American and https://en.wikipedia.org/wiki/American_(word)

From Wikipedia:

French, German, Italian, Japanese, Hebrew, Arabic, and Russian speakers may use cognates of American to refer to inhabitants of the Americas or to U.S. nationals. They generally have other terms specific to U.S. nationals, such as the German US-Amerikaner, French étatsunien, Japanese beikokujin, and Italian statunitense. These specific terms may be less common than the term American.
...

The use of American as a national demonym for U.S. nationals is challenged, primarily by Latin Americans. Spanish speakers in Spain and Latin America use the term estadounidense to refer to people and things from the United States (from Estados Unidos), while americano refers to the continents as a whole.

...

Generally, americano denotes "U.S. citizen" in Portugal. Usage of americano to exclusively denote people and things of the U.S. is discouraged by the Lisbon Academy of Sciences,[citation needed] because the specific word estado-unidense (also estadunidense) clearly denotes a person from the United States. The term currently used by the Portuguese press is norte-americano.
...

"American" in the 1994 Associated Press Stylebook was defined as, "An acceptable description for a resident of the United States. It also may be applied to any resident or citizen of nations in North or South America."

...

The entry for "America" in The New York Times Manual of Style and Usage from 1999 reads:

[the] terms "America", "American(s)" and "Americas" refer not only to the United States, but to all of North America and South America. They may be used in any of their senses, including references to just the United States, if the context is clear. The countries of the Western Hemisphere are collectively 'the Americas'.