The first ten inventors I see when I search for "US inventors" are:

Thomas Edison, Alexander Graham Bell, Samuel Morse, Eli Whitney, Nikola Tesla, George Washington Carver, Charles Goodyear, Lewis Howard Latimer, Henry Ford, George Eastman

... which does corroborate OP's "American inventors" hypothesis.

First off I think you searched for American Inventors not US inventors which seems to collide with African American because engineers are smart but computers are stupid.

Secondly google search results are a best guess based on prior search history and other data about you about what you want to read right now given a term.

You wont anywhere find a universal fact about what google themselves thinks about anything without reading material written BY google and not generated results from its search engine.