I'm not sure being called out for claiming that Detroit was once the largest city in the United States is "nitpicking." That's just a factually wrong statement,

I'm not sure being called out for claiming that Detroit was once the largest city in the United States is "nitpicking." That's just a factually wrong statement, and as a Detroit native, sets up a narrative (unintentionally, I'm guessing) that we fell from grace even harder than we did. "Detroit was once larger than New York City" is an implied claim that would unjustly amplify the collapse of Detroit to an audience that doesn't know better, particularly internationally. We fell, but not that hard. I understood your underlying point, but I don't think the correction is attempting to nitpick you, just striving for accuracy.