Best I can figure it, an anonymous webboard for economists used lousy identity hashing and some data scientists wrote a security analysis showing that fact. Part of it was showing that, surprise surprise, a bunch of economists at big name schools were posting a bunch of middle school taunts of women and minorities. (Not much to do with Mastodon here except just as one among many services that has IP address info of users.)
That's basically correct. The one other thing to note is that many in the profession are now wanting to use this to settle their personal and professional vendettas under a culture war aegis.
The other thing is that allegedly (I am not privy to any details so this is only based on what I've publicly read) the posters on that webboard had exposed some plagarism issues of one of the authors of the paper that doxxed them.
One of the coauthors also operates a Mastodon instance with over 5000 economists signed up. His complete access to these people’s credentials, such as IP address, email, and names, makes it easy for him to cross reference these people in the webboard. People are questioning if he intentionally set up the server to harvest people’s credentials for doxxing.
