@pan Well, you're reasonably private if you use Tor and only want to protect your original identity. So you have a perfect privacy setup for leaking sensitive information in a broadcast fashion to subscribers since (afaik) all !ostatus federating instances allow Tor connections.
But no, neither !GNUsocial nor # have any real privacy for hiding content.

There's always that question about which tool to use for what purpose: What's your threat model?