How would you accidentally leak your .ssh dir on Github?
I'd guess that most of us wouldn't do it by just "git init" in the home directory. There are many safer ways than that.
But we were all newbs once, and often even the newbs have access to various keys and credentials.
Not quite the same thing, but also a leak: https://blog.gitguardian.com/github-exposed-private-ssh-key/
I guess all these folks saying professionals would never make a mistake like this will also have insulting names for github engineers. :shrug