Funny anecdote, I have fond memories of Beastmaster from when I was a kid, and my 9 and 11yr olds have recently shown interest in Sword and Sorcery type media, so I thought I'd show it to them.
Note: I am French, naturalized US citizen and have lived in the US for now 18 years.
I checked the rating: PG.
I remembered it had Tanya Roberts in skimpy outfits, that Marc Singer was bare chested a lot, but mostly about the cool animals and freaky Vampire monster people.
Our whole family was watching happily (cept a moment of unease at first with the baby sacrifice scene and the half naked disfigured witches) when the slave women river bath scene happened.
Possibly NSFW though the image is censored
My wife's face and reaction were priceless, and even I was surprised that this had a PG (and due to the intensity of some scenes too).
Ah, the 80's and Tanya Roberts...
But yeah, in most movies it was fairly gratuitous. A John Landis movie, per example, was generally a 100% guaranteed close up shot of boobs if memory serves.