Gotta be the "high noon duel" in western movies. That didn't happen much in the real wild west.
Citizens shooting at gangs during bank robberies? Yup.
Shootout at The OK Corral? Yup.
Lynching of accused criminals before a judge could come to town? Oh hell yes.
But that trope of lawman/outlaw facing off in the middle of the street for a prearranged gun duel just didn't really happen.
Honestly almost all of it comes from a single duel Wild Bill Hicock had, and also a bunch of bullshit that a traveling huckster named Buffalo Bill Cody just sort of made up for fun in his touring wild west shows.
Actually yeah now that you mention it, it does sound like something out of a renaissance festival where they're setting up a scheduled show lol.
"Dirty Dave I'm calling you out! You and I are going to have a duel to the death! At 12:00 in the town square! Right in front of the Hootenanny Stage! Be there to see who is the winner! Tips welcome!"
An ancestor of mine wrote a memoir of growing up in an Old West mining town. He saw one gunfight. In the early morning, a man saw the front door of his house open and another man walk out. Not happy to find that another gentleman's bacon had been in his grill, he demanded satisfaction. That led to an impromptu duel which the offended husband won. My ancestor was walking to school when it all went down.
That was probably an exceptional situation, since the town in question was notoriously violent and corrupt.