Studies on Human Sexuality
Studies on Human Sexuality tend to be self reported data with no mechanism whatsoever for checking the claims of participants. The way to bet is that reports of wild sex lives as some kind of secret social norm are exaggerated or outright fabricated.
A lot of years ago, I was on an email list and something got posted and people complained that it required you to fill out a survey to access it. One smart alek who was a White male in his 50s said "I like being a 16 year old Black woman on such surveys."
So I know some people straight up bald-faced lie on surveys to protect their privacy if they feel "compelled" to answer your questions at all.
I think he did claim his actual PhD, but as a 16 year old minority. It was perhaps intended to be so ridiculous on the face of it that a good researcher should have thrown out that data point or flagged it for follow up or something.
Things are currently in flux and I have seen pieces suggesting actual flesh and blood people need to start making stuff up to protect us against AI, but historically it was generally accepted that people are typically more honest on the Internet than in meat space.
It has been compared to conversations on crowded trains in India where people in need of an outlet or feedback will tell things to total strangers they expect to never see again that they wouldn't tell to their best friend.
I don't really know why and I've never liked this about my life, but people meet me and over share like there's no tomorrow and I'm their new best friend forever. And I've spent a LOT of time online, including on Metafilter and Reddit which are LGBTQ friendly, BDSM friendly, nominally liberal spaces and I have not met huge numbers of people casually claiming to have had threesomes and blah blah blah blah blah.
So studies tend to say "Everyone has a wild sex life and your family and friends are just hiding the truth from you." Kind of like that song where the teenager says he can't wait to grow up so he can smoke and drink and make love on the kitchen table and then overhears his mom telling his dad she can't wait for him to move out so they can smoke and drink and make love on the kitchen table.
If all your closest friends are secretly having wild sex lives and successfully hiding it from you, who are they doing this with? Even the song says mom and dad are hiding it by NOT doing it with a kid in the house.
What is true is that there are people alive today who are roughly ten to twenty years older than me who came of age during the very liberal hippie era. Those people frequently had wild sex lives in their youth.
Most of them settled down, got married, stopped doing illicit drugs. I've talked to people who are that much older than me and their party days are typically long gone and if they still have the occasional threesome or whatever, it's like three times in the last decade NOT every weekend at some super secret party at their house that SOMEHOW the neighbors don't know about.
Reality: People having big social gatherings regularly at their home tend to get complaints from neighbors and the cops called on them even if there's no sex involved. They get noise complaints and complaints that there are no parking spaces available for anyone else and this is not typical usage for a suburban residence and you know it, so we don't want to hear your BS about a man's home is his castle.
The meme about men having an affair with the secretary is rooted in the reality that grown men and women have difficulty getting time alone together to get to know each other and establish trust, never mind have sex. The world over, people look askance at it if a man and woman spend too much time together.
It's not possible to regularly have a wild sex life and no one knows. If nothing else, your many sex partners will know and no matter how careful you are, other people will be aware you meet with people regularly under circumstances that are not the norm and are suspect.
I never had lunch with my doctor friend because he and I were both married and we knew that would look suspect though neither of us was looking to have an affair. We had a secret platonic friendship to avoid raising any eyebrows.
I complain about this on Feminine Character Works: It's challenging for a woman to establish herself in business in part because the usual coffee meetings or business lunches between men look and feel like a date to everyone, including the two business people having the meeting who can end up uncomfortable with it.
So conservative cultures and conservative individuals err on the side of no appearance of impropriety and we tend to not trust people trying to set precedents that men and women can spend time alone together for business purposes with no safety measures in place because they are probably up to no good.
The current status quo where people buy this idea that that "studies show..." when we know this is not some hippie era and we have social trends like incels doesn't pass the sniff test. Sorry, that's a NO from me.