I was thinking about why Wingdings, a popular phenomenon in Word docs, didn’t translate into the web, chat, and mobile SMS until the iPhone let us add the Japanese emoji keyboard.

The technical difference that I can see is that Wingdings is mapped to English letters (I.E. the same code points), whereas emoji are mapped to their own code points. So while Wingdings are typed using the standard keyboard, emoji (still today) requires a dedicated program/menu/keyboard to select them.

Additionally, font is often ignored/lost in transmission, in things like email, web text boxes, SMS. So what made emoji just work is that it used unique code points, not reusing other characters’ code points.