Thanks for linking that. I agree that whether or not stepping down was voluntary is an important question. But the answer is right there in your link. That whole memo is nothing else than a manifesto saying "Brendan had to go". Your only possible counterargument seems to be that the memo might have been just a PR move, while in fact he stepped down voluntarily. But, when you think of it, publicly saying "Brendan had to go" is not much different from actually making him go in the sense that in both cases the organization makes a bold political statement on behalf of its employees, its contributors, its supporters and with consequences for its users.