I don't think this needs a TW. If yes I will edit it.
Anyways Time has a chart of Oscar winners from 1970 to 2012 and compare them to todays. One section is on sex.
Female nudity is 4 movies this year, male nudity in 3 and masturbation is in 3. Sex standing up in 2.
Last female nudity was in 2006 with The Departed, Crash year before. No nudity prior until American Beauty in 1999 which had a trifecta of male nudity, female nudity and masturbation. Only one film one for sex standing up and that was the English Patient.
13 films from 1970 had female nudity 7 had male, only 2 had both which were American Beauty and One Flew Over The Cuckoo's Nest.
Long stretches of no nudity at all. From 2000 until today only 2 and both were female. Time also breaks it down for other aspects like violence, settings etc.