In the golden era of hollywood, beautiful people were generally selected for, as this fit the escapist fantasy notion movies were supposed to be.
Then somewhere around the 1960s maybe, the "ordinary" guy/gal (think Dustin Hoffman in The Graduate) became the "in" person to cast, someone the ordinary guy/gal in the audience could relate to.
Then, hollywood, being the BS hype machine that it is, began to proclaim that these ordinary people were, in fact, beautiful (especially once the Plastic Surgery machine could assist). Personally, I am sick and tired of seeing someone like Jessica Parker or Julia Roberts being touted as beautiful and gorgeous, when they are "ordinary" done up to extraordinary degrees.