The real situation is that you've granted me SSH access to your server but block anything than the OpenSSH client and I would like to use Go's crypto/ssh.
And it's one thing when they're two OSS implementations but when those alternative clients are your competitors it starts looking anticompetitive.
You giving me SSH access to your machine gives me the ability to use your infrastructure and resources for my purposes. Make the example instead you giving me access to an internal API.
You're focusing on the mechanism of my example rather than the effect. Apple hasn't given Beeper (or me or you) free access to their infrastructure. Shutting down Beeper using an exploit is well within their rights.
The real situation is that you've granted me SSH access to your server but block anything than the OpenSSH client and I would like to use Go's crypto/ssh.
And it's one thing when they're two OSS implementations but when those alternative clients are your competitors it starts looking anticompetitive.