Parisians are rude in the spring and summer, when Paris is overrun by tourists. I can't say I blame them, I found the tourist situation in July insufferable. In the fall I've found Parisians as nice as anyone else in a huge city. I've never found New Yorkers particularly rude, especially nowadays.
I'll second that, as a New Yorker who works in midtown I see tourists all the time. Mostly people ignore them, often we give directions or advice (like don't stop in the middle of the sidewalk, don't leave your purse on the subway seat, this train doesn't go west 4th).
Most visitors aren't used to having so many people around them. Just be mindful of your surroundings. Probably good advice for any city.
