Hollywood rationality is a popular stereotype of what rationality is about. It presents "rationalists" as word-obsessed, floating in endless verbal space disconnected from reality, reciting figures to more decimal places than are necessary, or speaking in a dull monotone. Hollywood rationalists also tend to either not have strong (or any) emotions. When they do, they often do not express them. Needless to say, this has nothing to do with actual rationality.
TV Tropes independently invented this exact concept and called it the Straw Vulcan. Their explanation is more detailed and has more subconcepts and better examples than ours, so if you want to know how to spot bad rationality as seen in popular media, you should probably check TV Tropes. (Warning, TV Tropes.)