Every medium has precedents. Social media came out of everything from bedroom sleepovers to water-cooler gab and social shopping.
What about Twitter? Post-It notes gone public? Maybe.
A better possibility is the bumper sticker. Especially the ones that reflect self-expression rather than just group identity. Especially slightly snarky ones—the bumper snickers.
“My kid is an honors students and the president is an idiot.”
“Lost your cat? Look under my tire.”
“I bet Jesus would have used his turn signals.”
“Grow your own dope: Plant a man.”
Whom do these serve? How?