It wasn’t even taken down. The dude was raided probably because of some electronic crime, they took his electronics to get evidence. Completely reasonable.
On their backup hard drive happened to be a backup a mastodon instance, so by extension they got that too. The backed up data, not the server.
It’s not some nefarious collusion, it’s completely reasonable actions.
Now whether the backup should have been stored unencrypted on a hard drive at their house? Well that’s a server admin problem not an FBI issue, but the comments here come across like the FBI shouldn’t have done what they did.
But I’d argue that you should not store anything on Mastodon where it would be an issue if it became public. It’s basic 90s internet safety. We know that the data isn’t encrypted (the same for Lemmy), don’t go sharing passwords on a site designed for public sharing.