The person who @'d the Epic org owns very little of the blame, in my opinion. If you have a button that causes 60m+ emails to be sent, and you leave it in a public place with no warnings and no confirmation dialogs, that's your bad choice. The person who presses the button is incidental; someone was going to.
They are not to blame for the email storm they caused. But they are still to blame for aggressively @-ing those developer groups not once but twice in a row for an insignificant PR. That's bad form, no matter if it causes an email storm or not.
