Agreed. He used an account trivially tied to himself, and posted publicly with his full name and picture on his blog explaining what he did, after having complained about the existence of this problem in public in the past (though apparently not specifically about Github).

He might have been stupid to do this, and a bit childish in his approach, but he did not go about it in a way that's reasonably interpreted as malice.

As a Github user, it angers me that they've responded in this way.