Got to love them massive caches.
Honestly who thought it would be a good idea to cache everything from every other server everyone on your server follows?
This level of redundancy is such a massive waste of resources and is hemorrhaging money from server hosts. And its all for the sake of garbage.
At the very least you should be able to control what does and does not get cached.
Maybe its ok that users avatars from other severs has their avatar still live on the original server. I don't know why I really have to say this.
There I said it