Have you tried expanding out of Anglo-Saxon culture? Here in France, flirting is a more common and comfortable mode of interaction, a form of adult politeness, without the underlying cultural codes that make it awkward in the US.
Painting with a coarse brush: Americans value childhood over adulthood, equate sex with violence, and polarize gender roles. The French value adulthood, see sex as a refined pleasure, and tolerate emotion in men.
A lot of this might be very cultural.
Sources:
Clotaire Raspail, “Culture Codes”
Personal experience: 23 years in the US, 23 years in France.
In that case, the only failsafe will be the human link in the chain. Having an actual person meet another person in the flesh will become the basis for trust, rather than encryption.
Not a terrible outcome, for humans. The machines will pay us to have meetings for them.