I haven't grown up with experience in purity culture. I was lucky to have parents that were open and accepting, as well as schools which taught not with a motif of shame, but of caution and respect to us as young adults. The only reason I really know a good amount about purity culture is because of the internet, and having friends who grew up in this kind of environment.
As many people do not know what purity culture is, it is an ideology within more conservative Christian sectors which puts emphasis on not having sexual relations before marriage and promotes strict modesty standards, especially for young women, regarding clothing and behavior.
There is nothing wrong with choosing to wait until marriage, as everyone's sex lives is their personal business, but it is the way abstinence and purity is taught in this culture that is harmful to both young women and men, specifically the idea that women are less pure or valuable if they choose to have sex before marriage, or that men have little self control when it comes to sex.
Of course, it's not only in this specific conservative subset that these ideals are preached. A popular comedy show on Netflix, "Jane the Virgin," starts off in a flashback of main character Jane as a young child, depicting her grandmother showing her a flower, and then telling her to crush the flower while claiming that the flower essentially represents her if she chooses to have sex before she gets married.
I've heard so many instances of girls being compared to objects such as bicycles, flowers, unwrapped candy, and being told that, much like objects, they have the ability to be "ruined" and "used" because they didn't dress modestly enough, or chose to lose their virginity at the "wrong" time. When I was younger, I saw a video on Youtube where a speaker came into a middle school classroom with a paper heart. Using scissors, he cut off parts of the heart, claiming that each time you have sex with someone you give part of your heart away, and it impacts your ability to truly love the person you were meant to marry.
Here's what's wrong with this. People are not objects. We are complex and nuanced, with the ability to love more than one person in our lifetime. It is incredibly damaging to a young girl to imply to her that the most valuable thing about her is her virginity, instead of her heart, her goals, and her humanity.
It is also disingenuous and insulting to young men to believe that all they want from a woman is to have sex with her, or to push the viewpoint that men in general can't refrain from harassing a woman depending on the clothing she's wearing. Men who are good people are not like this. And it can also be damaging to a young man to teach him from a young age that sexuality is something to be ashamed of.
People should be allowed to accept that their sexuality is a part of them, and make their own decisions without feeling pressure or shame. The only time I think someone has any business in someone else's sex life is to make sure they are informed on how to be safe and respectful.