I think there's some truth to the idea that people smell fear and hesitation, even from inside their air-conditioned cars.
When I'm running late, or am on a serious mission to get somewhere, the adrenaline kicks in, and my fears about heavy traffic and looney motorists move into my subconscious, where they only function to keep my instincts sharp and get me there alive. In those situations, maybe I'm just too focused to notice, but I don't recall any more beeping, kids yelling out the window, cars zooming too close, etc. than usual...Possibly even less.
Most of the time I like to ride casually, enjoy the peace and quiet, take back roads, etc., just as a matter of preference. Thus, I think I might give off more Sunday Driver vibes which would trigger predatory motorists' if I were in heavier traffic.