I think signal approach is the best. You can't be forced to turn in something you don't have.
Signal uses an OTR variant (I believe OTR masks the identity of the sender/receiver) -- not sure how thorough their implementation and protocol are[1]. Although if authorities already have the IP of one user they might gather a list of contacts.
So long as a company exists in a world controlled by US/European finance or is in their borders, they can be compelled to log what they are told to.