@eriner @amerika @p @FranciscoScaramanga @GummyNerds @PNS @sun I think it sends out a request for every object ("post") to every federated peer in the "nuking" instance's peer list. Basically the worst way they could have done this.
User deletes might be unique, because some part of the object has https://instance.tld/<user>#delete or something similar.
It's been a long time, since I looked in to this. @p might know more.