> If it does, it becomes an ethical maxim to use Tor.

This is one of the reasons I use Tor. If there is such a list, I want it to be full of people doing ordinary stuff. In effect, I want the list to be useless.

Indeed, this is the main reason I'm using Signal (and badgering my friends into using it). I want to increase the volume of encrypted non-sensitive stuff, so that the "list" doesn't have predictive value.

Having metadata (i.e. who communicates with who at which time etc.) still has lots of value for the three-letter agencies (some even say it's even more important then the content of the messages itself). As far as I know Signal does nothing to avoid this kind of metadata (but please correct me if I'm wrong).