OK, such a knowledge problem might not be computationally solvable in principle.
It doesn’t have to be.
One muddles through: Is there any doubt that Tor’s and Bitcoin’s relatively secure software distribution has made the job of global adversaries harder?
There are degrees of security, and maybe perfection isn’t possible.
The best objective metric might be how many unpopular people can use them with impunity. (Note 1.)
Restating my earlier point: A bazaar of “SAFE” apps put up willy-nilly is a disaster waiting to happen, since it makes the job of crooks and states (but I repeat myself) much easier.
Note 1: Some of those unpopular people, I would readily consign to a furnace, but I assert that one can learn valuable lessons from their being at large, since it might be, for mathematical reasons, the only objective measure we can ever have:
and more info on the same operation:
Only 72 charges were filed against the approximately 600 members of Dreamboard due to the extensive encryption involved.
Twenty of those charged, however, are only known by their Internet handles, and as such were each individually charged as John Does and remain at large.