When A Fistful Of Dollars first aired on ABC, an exclusive prologue was added to set up the story – but ruined the mystique of Clint Eastwood's Man with No Name in the process. During the heyday of the Western genre, audiences wanted uncomplicated tales of good vs evil led by heroic figures such as John Wayne. There were exceptions of course – such as Wayne's own The Searchers – but on the whole, there was little in the way of moral murkiness to the heroes. That changed in the late '50 and '60s, especially with the arrival of Sergio Leone's Dollars trilogy.

https://screenrant.com/fistful-dollars-movie-tv-edit-prologue-clint-eastwood-no-name-hero/