A while back a spam war between @fulltimegeek and Bernie developed over a refund due @fulltimegeek which @themarkymark sent to @null instead. The #irredeemables list was created to totally censor all @fulltimegeek's accounts, and Bernie apparently now is able to use @themarkymark's sole option to control that #irredeemables list at will to censor anyone they want, without any limitation whatsoever.
I think the shortest route to the actual event referred to above would be to search for @themadcurator, which ceased posting around that time due to it's being a casualty of the conflict.
Stinc itself created the list, which prevents posts from listed accounts from being available to dapps using its APIs, (which includes all of them generally in use by affected communities) and now @themarkymark administers it for Bernie as best I can tell.
I remember that spam war!
If I recall correctly it broke out right around the day I tried to get some help from @fulltimegeek with doing Steem stuff in Java.
Horrible timing for me; he basically disappeared after that and I got no help from the only person I could find with any Java experience on Steem.
Wow. Was not aware of that backstory.