Signal fans like to selectively forget that the server-side is proprietary software - therefore, the whole platform can't quite be proven to be reliable.
Essentially, they are not much better than Whatsapp stans.
That’s hilariously wrong, the server source code is at https://github.com/signalapp/Signal-Server. How can you make such a claim in good faith when it’s so absolutely trivial to refute?
I don't need the source code for Facebook.com to know what information my open-source browser sends to it. Same concept with Signal, you can read the client source code to know what the protocol sends to the server.