I would never use the word "adorable" to describe sex. And I'd say that it's a big mistake to say that "sex is totally wonderful in every aspect". That's not true at all. I'm pretty sure that sex slaves at the very least would disagree with that point.

I'm not really sure which cultures you're referring to, but in America at least, sex itself is not taboo, talking about it openly kinda is though. Lots of people, everywhere are having sex. It's just when it shows up in popular culture that people start getting uppity about it. But even in America, sex and sexuality is pretty prevalent in mainstream media.