I was taught, many years ago, to assume will make as ASS of U and ME.
That was years before Sex & the City, decades before Tinder. Casual hook-ups and loveless fuckbuddyships were happening, of course, but they weren't the norm at any age. So the danger for most people was to read too much into what could be casual flirting.
What my head understands--but my heart does not--is how people can have sex with people they don't even like. Yes, I understand the itch and the desire to scratch it, but that's what masturbation is for.
I'm no prude, no arbiter of morals. I'm not even convinced anymore that monogamous marriage and nuclear families are a tenable model to build our society around in the 3rd Millennium CE. But sex outside of friendship just feels awfully risky to me, emotionally. And way more lonely than just jacking off.