@henry I'm going to risk my own instance getting defederated for writing the following.
Root cause of all fediverse spamruns is instance owners not knowing themselves. If you run an instance alone and allow for open registration??? Yeah... sorry you should not be allowed to do anything on the internet but browsing web pages.
Today I suspended an instance hosted on a Synology NAS. Just one example of many that just makes my jaw drop.
cwnbr