Well this escalated so quick, why would Snowden use it when he was running away from the US in these past years. Also Appelbaum used to be a serious hacktivist who was against NSA surveillance but pro-Signal, something is missing for me : why would early adopters like cryptographers, cypherpunks and security engineers advocate for a technology funded by FBI. Signal seems to be a spinoff of Whatsapp(Brian Acton) more than Radio Free Asia, simply because of their medium. To what extent can we use products that are Government Op, for instance the internet was a military government project, as long as we are able to have secure encryption that is transparent, I think that's way better than the Facebook monopoly. The best scenario here is not to use any of them of course.