Musk has been talking about integrating Grok into Tesla cars and also adding a lot of space and rocketry specific training. It is completely possible that these models were trained on data that would logically be public at some point. It is also possible that the author's guess is right and that these were to contain sensitive data. Noone really knows, but honestly, these kinds of mistakes are happening all the time.…
How would you accidentally leak your .ssh dir on Github?
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