Sex, as long as enjoyed and within the consent of both people (in a clear state of mind) is their own choice and business, regardless of age, genders and fetishes they may or may not enjoy. For all I care, I don't see a problem with fourteen year olds having sex. Or gays, bdsm, other fetishes... Laws should strive to keep the balance between both people having a fair choice, nothing more. (imo)
(in a way this raises questions concerning prostitutes.)
In history, society has always oscillated between 'very sexual' and 'unspoken and unheard of'. The romans had a very open, sexual society for quite a while, and their civilisation could easily be considered far greater (but how does one measure?) than atleast 5 ages after the fall of the roman empire, during which time a pope cut off the genitals off the statues just to hide them. What makes the sixtees so much worse (society / morality wise) than the other decades in last century?
I do think the media is often oversexualised, as is perhaps our youth, me included. By that I mean it's everywhere, and i'm sure i've already seen more than the avarage person would in his entire lifetime before 1950. This may be a bad thing within relationships and regards the 'value' of sex.
As for sex not carrying repercussions or responsibilities... Unless you're a rapist, GOODLUCK. The only sex without repercussion or responsibilities is the sex you have with yourself. As soon as you involve other people, they'll have expectations (both during and after the sex.) Sometimes these will be low or even the hopes of never seeing you again (one night stands), but more often they'll be less simple to satisfy. Just because we all like sex, doesn't mean we all have it with eachother without any strings attached. There's no such thing as free sex (unless you're both drunk too drunk to remember the next day.
). Having sex with good friends, for example, is usually a terrible idea.
Note that i'm talking about sex. Not about the production of new humans, nor about starting families. I know this is probably exactly your point, however the diffrence is called anticonception / birth control.