I remember making a similar post about this on some other forum in the past.
According to my university textbook on worldhistory, what is morally acceptable concerning sexuality depends on factors as over- or underpopulation, resource and ground shortage/abundance, food shortage, diseases,..
For example:
- Different forms of polygamy being more common in areas where large families were seen as more important.
- The Catholic church in Europe only took an anti-sex stance (end 16th century if I remember correctly), when ground shortage became a problem. Promoting celibacy, condemning outside marriage relations, linking sexuality with sin,...
- Homosexuality, that was in the past not uncommon and not seen as negative, that as a result of this changing view becomes seen as dirty, immoral, degenerative, harmfull and a mental disease. Basically the same words that get thrown around with similar subjects. With potentially harsh punishment or even death penalty for breaking such rules in the more extreme cases.
IMO, the rising of the age of consent is based on the same principle. Simply one of the results of overpopulation and a society that naturally responds to that. Propagated by religions and morals that nobody is supposed to question. I can't understand how someone can be a respectable member of society in one civilised country, but be a monster in another country for doing the same thing, a sexual relationship with an adolescent (a word that conveniently doesn't get used, they're all "children" now).
In my country 16 is the legal age and 15 is the average age one loses his/her virginity. IMO the legal age should never exceed the average. They are obviously already active and (not surprisingly) there are no exceptional issues here with teenage pregnancies, STD's and certainly not trauma's. These problems happen because of other reasons, like bad sex-ed (starting too late, abstinance,...), low living standards and a society that makes people feel like victims.
Neither would I expect to see an increase in sexual activity at an earlier age then now. Even so, it will quickly find a balance and that is where the line should be drawn. Neither is it degenerative or immoralising or whatever other nonsense. I don't see any arguments that can be given for that, other then dogmatic ones.
Putting a limit on it makes it more tempting, it doesn't take away the urges that are naturaly there towards young people who are already fertile. But on the other hand it does push things underground where there is less overview. And it makes people do more "desperate" and potentially harmfull things to satisfy their needs while otherwise they wouldn't have to and could just pick up a willing partner. It puts people in prison because they were a couple days too early to make out with their girlfriend and got caught, having their lives ruined and more likely to become real criminals later in life since, for example, getting a job after many years in prison would not be very easy. That's just taking things to an extreme, which always ends up harmfull.
Limiting 2D art goes even further in ridiculous territory. That's just a witchhunt, it already is in some cases.
There is a more personal reason why I follow this way of thinking as well, which is because of my mechanistic view on the human mind, with the reproduction instinct as the overarching programming in the brain. We all have a competitive drive in ourselves, favored by evolution and in service of this reproduction instinct, which gives rise to feelings as jealousy, greed, anger,... Increasing the limits on sexuallity would increase the competitiveness since it excludes a relatively large amount of people, resulting in more jealousy, anger, greed,... Obviously, this is a part of my view on the working of the brain, so this will not be something everyone agrees with.
In the end it's just sad that most people can look at many cultures, past and current, and see something that they find incomprehensible or simply horrible, often about sexuallity (what a coincidence...), but at the same time not being able to look at their own culture and see that extreme things can happen there as well.
But since the overpopulation won't change anytime soon, I don't expect the direction of increasing sexual restrictions to stop either. Or maybe I'm wrong and society can actually overcome this for once.

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