This article points to some of the real risks of federated social media. You need to trust your admin and be aware that, if they decide to stop hosting a node, you lose your account and all your posts.

I still think it's better than the alternative. Decentralization has always been the strength of the open web. And, if anything, this speaks to the need for having lots of small or medium-sized instances, rather than a few huge ones.

http://xn--rpa.cc/essays/infrastructure