Adding the Bitcoin symbol to the keyboard will scream "ADOPTION". The question is where to put the key? I would suggest they replace the $ with the bitcoin symbol... just kidding. However, it gotta go somewhere, what do you think?
I think other people are right with what they have said, there is more possibility of it being added through emojis, but we don’t know whether they would be officially added to the keyboard button where you can find the dollar, euro and other currency symbols. I even used to think that the bitcoin symbol has been added, but that maybe it wasn’t just available in my country yet. Because, I once saw a news that said that Google keyboard now has the Bitcoin symbol on its list of currency symbols.
So, I thought that it has been available for years, until now that I’m seeing this topic or thread. Anyways we’re just going to wait and see whatever they would want to do about it, if they decide that they’re going to add it, then it’s up to them. For me it’s not really necessary, whether they add it or not there is still going to be an adoption for Bitcoin.