The product specialist at the auto show may in fact be a lovely woman, but she’s not there to serve as eye candy. (Okay, she’s not there just to serve as eye candy.) She’s got to know the product line cold, if only to stay ahead of the wise guys who think they can stump her. (See, for instance, this one, who epitomizes the current standard.)
Turn the clock back a few decades, and there’s less emphasis on product knowledge and more emphasis on being decorative. Mandated clothing was generally either scanty or scantier. And Curbside Classic has photographic evidence of one particular show where two of the young ladies well, okay, they might have been wearing earrings. Hard to tell at this distance.