I think it is striking how much and how often this crowd of Go enthusiasts also displays an intense interest in language, wordplay, and communication. I believe this is more than just a coincidence of overlapping passions, but rather something about the nature of the game that attracts like-minded people that are more interested in linguistics (and perhaps also music, but then again, nearly everyone “likes music”).
An old metaphorical name for the game is 手談, which literally means “hand talk” and refers to how the players converse via their moves. I’ve heard many examples of players echoing this sentiment in discussing how they feel they can express themselves and expose something about their personality in how they play the game. Moves can convey a sense of character and style, whether calm and peaceful, carefully negotiated, shrewdly transactional, or all-out aggressive and violent. Some have even compared certain plays to flirtation and romance.
Key features of Go makes the game particularly expressive, especially in comparison to many other abstract strategy games, where I don’t think analogies to communication are made nearly as often. The vast number of playable choices and relatively long duration of a game yields many different playable paths that allows the game to be so expressive. Also, the abstract minimalism of the mechanics offers a neutral canvas that avoids the thematic connotations that can come from superfluous styling (like castles, cavalry, clergy and royalty).
The interaction and expression in a game of Go is a form of communication that makes playing like using a nonverbal language. I was inspired to write about this by the below TED talk, which makes an analogous argument for music as a nonverbal language.
Even though the speaker is talking about music instead of Go, I think (by way of analogy) he does a better job than I could in further explaining my point. However, to understand one needs only to experience the game of Go.
TL; DR: Go is a nonverbal language like music.