The headline is kind of misleading. I'm not sure that anyone who'd considered the subject thought they were at all private if they used the system without tor. Bitcoin.org surely suggests no such thing.
Fair enough. The interesting part for me was Tor being easy to block. I have never heard that before. I guess I also found it surprising that it was worthy of a study at a cryptography/ security department.
We specifically added direct support for tor hidden services as one tool to deal with tor exit banning. HS inbound peers are not banned persistently. Lots available to improve here, though at least tor is enough that you can't be screwed over without your help (E.g. turning tor off if you get dos attacked), for advanced users this is at least a basic level of capability.
