@parleur Yeah sure:
It ties your activist actions to your real-life identity (and family/friends).
It keeps a record of every mouse movement, click, location and everything you type forever (even if you delete it)
It stores all your contacts and all their contacts and all their movements and interactions.
It knows a lot of sites you visit off of Facebook through their "like" buttons
If you're an activist this is very valuable data that can easily be used against you.
mastodon.parleur.net is one server in the network