It doesn't need to be added to the keyboard exactly? Even local currencies don't have its own symbol on the keyboard. Maybe when it has the same level of authority as the $? Though honestly with it being decentralized, I highly doubt it would only take that, it'd probably need a lot more. Undisputed at that level I supppose?

Wouldn't you think that at that point it's screaming that it's already been adopted instead? Being on the Keyboard as its own logo would mean that it has a very solid reputation overall on the global level. Much so that there's no need to introduce it to most people, they'd already know it.