If a competitor to you comes up, and starts building a server around this client, they can start diverging from this client without upstreaming these changes.

If a competitor to you comes up, and starts building a server around this client, they can start diverging from this client without upstreaming these changes. It protects you, future users, and makes this protocol live beyond the age of any single company! Its argubly why git hasn't gone away despite its shortcomings. And while it has been commercialized, it hasn't significantly diverged.