Sex today is more open, apparently on some internet sites, very open, but I don't know first hand.
But the thing is, while today there are still scandals about politicians getting involved with women they are not married to, or in some cases even hookers, there is not a lot of scandal left. If two people married to other people have affairs, it can be a local scandal, but the people are rarely ostracized. Large numbers of babies are born out of wedlock every day. Even religious people, hopefully, don't condemn them or call them names. People who live together today are rarely ever condemned, I don't say they should be, but it was done just as recently as the 1960's.
In those days, of the "Scarlet Letter', any sex outside of marriage was a crime. An illegitimate child was always called a certain B---- word and had few if any rights. They might be treated worse than even their mother, even though they had nothing to do with it.
Since there is birth control not to mention Viagra, etc. there might be more sex, there are more people by the billions than in 1700's. That is impossible to say for sure. It has more to do with society's view of sex.