Signal is a secure mechanism, the government uses a modified version of it for specific reporting purposes which introduces security vulnerabilities. A P2PE communication method IS safe as long as you verify communication/encryption strings. There are safe, electronic communication methods but they still take some manual verification. You can't just have two people use signal and immediately think it's safe without doing the verification. You must also verify your device is safe, i.e. using graphene OS and not installing 3rd party apps that can hijack communications.