While it's true that we (you and I) do not consider fornication and homosexuality to be moral, a very significant percentage of our fellow citizens does.
In the case of homosexual activity, I don't think that an absolute majority of the population finds it acceptable. However, an overwhelming majority of the population, including the FR sample, does not believe fornication is wrong.
These are massive changes in beliefs over the past 60 years, and they cannot be attributed to the greater reproductive success of sexual libertines. Most people have converted from the traditional religion of Christianity to the new religion of untrammeled sexual gratification.
For that matter, 85 years ago most people thought contracepted sex was wrong, even for married couples
The NEW TORK TIMES ran editorials against legalized contraceptives in 1930. Truth.