If you go to the community page and hover over a name at the bottom of the page, you can see how many followers the user has. I noticed that one of the most badged users inactivated their account, and showed a zero next to it. Hovering over the 0, you can see the username of the unactive account, and clicking on the zero shows the regular "[User]'s Followers" page, with no names, obviously.
Not sure if this should be considered a bug, or what the policy on inactive accounts is here, but I figured I should make a note!
Paging mk for input.