It's not strange, really, but there's an American archetype I don't think there's a snappy name for but which I'm convinced is real. I'm talking about a particular type of middle-aged American man who's seen as cool and clever and aloof in a grounded, everyman sort of way, e.g. the Steely Dan guys, Warren Zevon, Harry Dean Stanton, John Lurie.
You could chuck in people like Bill Murray and Norm Macdonald too, although Bill Murray's a bit too overtly eccentric at times. Tom Waits is almost one, but he tries too hard. Steven Wright. Elmore Leonard.
The dress sense is important. They don't care about looking good or cool, which adds to people's impression of their coolness. Scruffy suits, sports caps, maybe balding with not much effort to do anything about it or hide it, shirts and jeans, dad trainers.