As much as the keys contain public data, I wouldn't consider (but it apparently is) the list of keys with access to my github account public data. Github willingly reveals information about pseudonyms, etc.

This is a data vs metadata thing, the data is public, but who it belongs to, and what one can do with it need not be.

Though it may be incredibly impractical or theoretically impossible, depending on the key and time of day, there is always a possibility that a public key can be used as an attack vector to guess a private key.