I don't know what age Bogie and Bacall were, but wasn't that really the 40's? I'm thinking more of the high school/college romances with Doris Day and various forgettable males. Beach Blanket Bingo?
It *was* actually the 1940s, but aside from films about teenagers (which you have to admit are more likely than not to be biased towards relationships among people roughly the same age), the notion that "mass media, particularly the movies" have somehow been discouraging age-gap relationships is pretty funny.