I can't believe that 88% of men and women have sent images of genitals. I've never heard of that in my life.
But, the only clue lies in the fact that an acquaintance of me from Australia has said "It's common in Australia to talk about sexual issues between different sexes."
Tens of years ago in Japan, it was common in Japan's companies that elderly men slam young female workers with sexual words.
For example, if there is a woman with full breasts, they used to say "How indecent you are?".
If there is a woman with good looking face, they used to say "You must have hired as a candidate of expected wife of someone in our company rather than because of your skill."
But, these statements are banned recently as "sexual harassment" in Japan, needless to say sexting.
On the other hand, isn't there law to punish them in US?