Date: June 08, 2018 01:35PM
Excerpt from http://www.ldsliving.com/R-Rated-Movies-What-Have-the-Prophets-Actually-Said/s/82659
why they don’t watch R-rated movies, their response will be some variation of “because the prophet said not to.” But follow-up questions (Which prophet? What exactly did he say? In what context?)
In fact, the entire pantheon of past prophets has only mentioned R-rated movies in general conference once—three decades ago, in a 1986 talk by Ezra Taft Benson entitled “To the ‘Youth of the Noble Birthright.’”
“Tonight I would like to speak directly to you young men of the Aaronic Priesthood,” he started his talk.
"Don’t see R-rated movies or vulgar videos or participate in any entertainment that is immoral, suggestive, or pornographic (emphasis added).”
I find it interesting that the counsel to avoid R-rated movies was directed specifically to youth (six months later, President Benson delivered nearly identical advice to young women), who often need more specific guidelines to aid their decision-making. It’s also interesting that this counsel is mentioned under the umbrella of avoiding media that promotes lust.
There you go they never said don't watch all rated R movies.